Our two build systems can generate almost entirely a modulemap file laying out
one module per library. Due to some non-modular implementation in ROOT's core we
still need to treat some header files specially.

This patch appends modular header files to the modulemap while skipping the
predefined ones. Configure-make relates all headers that are installed in
$ROOTSYS/include to their library whereas relates only headers which are part of
library's dictionary.

Fix problem switching interval in MCMCIntterval

Avoid misusing the existence of ROOTSYS to decide the type of installation. Make use of 'root-config'.

Extend the code to carve smaller logical pages from large physical pages
on machines that have large physical page sizes.

Since this class has been used for quite some time now without major
trouble, it doesn't seem imprudent to hide the status messages about the
mmapping strategy by default. Since I have had requests to that end,
this is what I do with this commit. BidirMMapPipe gets two static
methods which allow toggling the message back on if the user so wishes.

This patch introduces a cache for index codes into RooMappedCategory.
The previous implementation had to do a regex match on the different
category labels, leading to slow evaluation. We now keep a cache indexed
by the input category's index code, leading to a significant speedup.

The persistent data format of the class remains unchanged, therefore the
class version number was not changed.

Backports to the various ROOT 6 and ROOT 5 bugfix branches may be in
order.

In the RooDataSet constructor, the wrong TTree pointer was picked up
when the code is supposed to read from an external ROOT file, causing a
crash. This code fixes the null pointer deference by picking up the
right TTree pointer.

Backports to the ROOT 6 and ROOT 5 bugfix branches may be in order.

- spell check.

- Spell check

- Remove trailing white spaces and TABs
- Spell check
- Move some methods' headers at the right place.

- Remove trailing white spaces and TABs
- Spell check
- Move some methods' headers at the right place.

- Remove trailing white spaces and TABs
- Spell check

- Remove trailing white spaces and TABs
- Spell check

Clang implicitly builds modules upon seeing header files present in the module
map. Having cmath before alters the contents of the TU (by defining macros
which affect building the modules).

With traceEval return a const char*, it was return the content of a temporary object, and in this
case deleted memory

A lot of bugs were fixed since then. Now we want to find as many bugs in clang
as possible.

Return the correct ordered matrix in RooFitResult::reducedCovarianceMatrix also when the size is the same.

add a check for the size of the expected p values in HypoTestInverterResult::ExclusionCleanup(). This fixes ROOT-8049.

Fix memory leaks when reading RooFitResult and HypoTestInverterResult from disk. Patch from Geert-Jan Besjes & Ingrid Deigaard. Fix for ROOT-7986.

- Remove white spaces
- Remove TABS
- Spell check