Fixes #7561

Co-authored-by: Enrico Guiraud <enrico.guiraud@cern.ch>

This makes a difference for associative containers.  For reading the iterator are iterating over the
'TStaging' object rather than the collection.  For writing we need to iterated over the collection

The intent was to prevent the creation of sub branch with 2 consecutives dots
and to avoid a dot between the branch name of the collection and the underscore
for name of the index leaf.

The major problem of the first try is that the name of the top level branch
was changed from "t." to "t" making existing code search for the branch by
fullname failing.

Fix #7281

This effectively ammends/corrects d225f942

Before v6.23

******************************************************************************
*Tree    :tree      : treelibrated tree                                      *
*Entries :    10000 : Total =          485042 bytes  File  Size =     177202 *
*        :          : Tree compression factor =   2.74                       *
******************************************************************************
*Br    0 :t.        : Int_t t._                                              *
*Entries :    10000 : Total  Size=      83464 bytes  File Size  =      12844 *
*Baskets :        4 : Basket Size=      32000 bytes  Compression=   6.25     *
*............................................................................*
*Br    1 :t..fUniqueID : UInt_t fUniqueID[t._]                               *
*Entries :    10000 : Total  Size=      80935 bytes  File Size  =      12857 *
*Baskets :        4 : Basket Size=      32000 bytes  Compression=   6.25     *
*............................................................................*
*Br    2 :t..fBits  : UInt_t fBits[t._]                                      *
*Entries :    10000 : Total  Size=      80903 bytes  File Size  =      12879 *
*Baskets :        4 : Basket Size=      32000 bytes  Compression=   6.24     *
*............................................................................*
*Br    3 :t..e      : Double_t e[t._]                                        *
*Entries :    10000 : Total  Size=     121029 bytes  File Size  =      65937 *
*Baskets :        6 : Basket Size=      32000 bytes  Compression=   1.83     *
*............................................................................*
*Br    4 :t..t      : Double_t t[t._]                                        *
*Entries :    10000 : Total  Size=     121029 bytes  File Size  =      71633 *
*Baskets :        6 : Basket Size=      32000 bytes  Compression=   1.68     *
*............................................................................*

After the first try:

******************************************************************************
*Tree    :tree      : treelibrated tree                                      *
*Entries :    10000 : Total =          484998 bytes  File  Size =     177400 *
*        :          : Tree compression factor =   2.73                       *
******************************************************************************
*Br    0 :t         : Int_t t_                                               *
*Entries :    10000 : Total  Size=      83438 bytes  File Size  =      12838 *
*Baskets :        4 : Basket Size=      32000 bytes  Compression=   6.26     *
*............................................................................*
*Br    1 :t.fUniqueID : UInt_t fUniqueID[t_]                                 *
*Entries :    10000 : Total  Size=      80925 bytes  File Size  =      12852 *
*Baskets :        4 : Basket Size=      32000 bytes  Compression=   6.25     *
*............................................................................*
*Br    2 :t.fBits   : UInt_t fBits[t_]                                       *
*Entries :    10000 : Total  Size=      80893 bytes  File Size  =      12869 *
*Baskets :        4 : Basket Size=      32000 bytes  Compression=   6.24     *
*............................................................................*
*Br    3 :t.e       : Double_t e[t_]                                         *
*Entries :    10000 : Total  Size=     121017 bytes  File Size  =      66198 *
*Baskets :        6 : Basket Size=      32000 bytes  Compression=   1.82     *
*............................................................................*
*Br    4 :t.t       : Double_t t[t_]                                         *
*Entries :    10000 : Total  Size=     121017 bytes  File Size  =      71609 *
*Baskets :        6 : Basket Size=      32000 bytes  Compression=   1.68     *
*............................................................................*

Now:

******************************************************************************
*Tree    :tree      : treelibrated tree                                      *
*Entries :    10000 : Total =          485003 bytes  File  Size =     177402 *
*        :          : Tree compression factor =   2.73                       *
******************************************************************************
*Br    0 :t.        : Int_t t_                                               *
*Entries :    10000 : Total  Size=      83444 bytes  File Size  =      12844 *
*Baskets :        4 : Basket Size=      32000 bytes  Compression=   6.25     *
*............................................................................*
*Br    1 :t.fUniqueID : UInt_t fUniqueID[t_]                                 *
*Entries :    10000 : Total  Size=      80925 bytes  File Size  =      12852 *
*Baskets :        4 : Basket Size=      32000 bytes  Compression=   6.25     *
*............................................................................*
*Br    2 :t.fBits   : UInt_t fBits[t_]                                       *
*Entries :    10000 : Total  Size=      80893 bytes  File Size  =      12869 *
*Baskets :        4 : Basket Size=      32000 bytes  Compression=   6.24     *
*............................................................................*
*Br    3 :t.e       : Double_t e[t_]                                         *
*Entries :    10000 : Total  Size=     121017 bytes  File Size  =      66198 *
*Baskets :        6 : Basket Size=      32000 bytes  Compression=   1.82     *
*............................................................................*
*Br    4 :t.t       : Double_t t[t_]                                         *
*Entries :    10000 : Total  Size=     121017 bytes  File Size  =      71609 *
*Baskets :        6 : Basket Size=      32000 bytes  Compression=   1.68     *
*............................................................................*

This test is also 'stressing' the interpreter and in particular the increase in the number of symbols.  This leads to a noticeable reduction
of the speed of the test (or more exactly the loading/setting up of the test).  In addition some of the nightly run on VM which can
lead to performance variance (at least on this test) of a factor 4.  In a good day on one of 'failing' vm, the 100 iterations takes 400s,
during the nightlies it oftens takes 800s to 1000s ... the timeout limit is 1200s, so it is reached from time to time.

Bring utility functions from TTreeProcessorMT in their own namespace, to make them available for internal use in other ROOT sources.

We want to warn users if a RResultPtr returned by a lazy Snapshot
action is destroyed before the event loop is run, but _only_ if there
are no other RResultPtr objects that share ownership of the result,
i.e. if there is no way to trigger this Snapshot in the future.

Test that we don't warn needlessly if a RResultPtr corresponding to
a lazy Snapshot action is destroyed _but_ other RResultPtr instances
share ownership of the result.

In order to specialize cling's value-printing logic for collections
we perform some SFINAE checks. Among other things, the checks
assert that `++(obj.begin())` is well-formed. That compiles for
`std::vector` and other collections with "fat" iterators, but does
not compile for collections that use raw pointers as iterators:

```cpp
auto beg(std::vector<int> &v) {
    return v.begin();
}

int *beg2(std::vector<int> &v) {
    return &v[0];
}

int main() {
    std::vector<int> v{1,2,3};
    beg(v) += 1;
    //beg2(v) += 1; // does not compile - beg2(v) is not an lvalue

    return 0;
}
```

Requiring instead `std::begin(obj)` to be well-formed should be
backward compatible and it should allow collections that use raw
pointers as iterators to also be pretty-printed by cling.

Co-authored-by: Axel Naumann <Axel.Naumann@cern.ch>

Update freesegments.txt to include 64-bit case and correct an off-by-one error in the description of fLast.

Update TDirectory.txt to include 64-bit case and the reinterpretation of Modified and Writable as a version.

Benchmarking showed that calculating the bin indices in ParamHistFunc on
the fly is faster than caching them in a std::vector.

The ParamHistFunc in the histfactory has a persistent std::map<int,int>
data member. It can be replaced with a std::vector<int> where the
previous key is the index in the vector. This is much faster.

Schema evolution is not a problem here. With this commit, the data
member is made non-persistent because it can be computed from other
persistent data members.

we have lots of proper usage now, and it would need to be adapted
to current TBB not offering task_scheduler_init anymore.

(cherry picked from commit 1bb8f9a0)

one implemented for histogram. the `v` field described here: https://root.cern/doc/master/classTStyle.html#aedeb1d117d9f16af9f8ad430bf956d64
was not working the same way. This PR implement the same behavior for TGraph.

- Fix typos

(cherry picked from commit 2aa4dd54)

This fixes TStatistic::GetMax() when all entries are negatives.
See https://root-forum.cern.ch/t/problems-with-getmax-in-tstatistic/44324

Profile directory name should be in Window notation

In such case browser will be run in headless mode and
short performance test will be performed.
Function will block until test completed or timedout after 30 sec

Before it was called as batch_mode, but batch used for other purposes

But Firefox still cannot be used in true batch mode for image production

Batch mode, which is now only supported by Chrome, allows to run
JS code loaded from file and dump result to output file - no any
communication with host application required

Now extra headless mode is introduced, which allows to run client
code in the headless browser and communicate with it. It was original
way to produce batch images, therefore need to rename some methods
to clearly separate from old functionality.

Idea to allow use such mode in headless browser.

(cherry picked from commit 2b7dd0cd)

was only needed for rfio which has been dropped.

The original directory was removed.

* RLogScopedVerbosity doxygen doc was not visible because source code was under ``` instead of ~~~

* [foundation] RLogger doc (NFC) - thanks, Sergey!

Co-authored-by: Axel Naumann <Axel.Naumann@cern.ch>

* Next bunch of changes for Win64

 - Use different typedefs for (U)Longptr_t to prevent overload errors on Win32
 - First round of replacing (U)Long_t with (U)Longptr_t where applicable (mostly on core) and fix the following kind of warnings (leading to errors when truncating pointers)
   `warning C4311: 'type cast': pointer truncation from 'void *' to 'Long_t'`
   `warning C4312: 'type cast': conversion from 'Long_t' to 'void *' of greater size`

* Better fix for pointer formatting

* Fix compilation warnings

* Apply Philippe's suggestion

* Try to fix 32bit/64bit pointer formatting using %zx

* Try to fix a compilation warning

Try to fix the following warning on `ROOT-debian10-i386/cxx14`:
```
warning: format ‘%zx’ expects argument of type ‘size_t’, but argument 4 has type ‘Longptr_t’ {aka ‘long int’} [-Wformat=]
```

For example this fails on windows.

Significantly reduces size of includes in header files
One has to include json.hpp where it really used

Can be used as forward declaration to reduced includes sizes