Allow --enable-cint7 to build CINT7 in parallel to CINT5.
This builds root7.exe, rootcint7, cint7 which will pick up libCint7.
CINT includes are now in include/cint and include/cint7. Many #include
statements changed because of that. We still provide backward compatible
wrapper headers in include/ pointing to the include/cint ones.
Dictionaries for CINT5 and CINT7 are now (mostly) compatible.
When --enabled-cint7, TCint for CINT5 is in libMetaTCint and TCint for CINT7
is in libMetaTCint_7. The classes' source is identical for now (except for the
cases marked with #ifdef R__BUILDING_CINT7); they pick up different CINT
implementations, though.
Without --enable-cint7, TCint.o is linked into libCore, just like it used to
be. With --enable-cint7, TROOT() dlopens libMetaTCint / libMetaTCint_7,
depending on which libCint the binary is linked against (determined via
G__cint_version). TCint contains and sets a global factory pointer that
creates the appropriate TCint object for TROOT.

The cintdlls are built for CINT5 and CINT7 separately, cintdlls.mk is
included twice, with different contexts set by cint/Module.mk and cint7/Module.mk.

--enable-/--disable-cint7 (i.e. (TCint.o in libCore vs libMetaTCint)
triggers a re-build of TROOT.o

Remove dependency from TGWin32ProxyDefs to bare CINT
Add implementation of G__alloc_tempobject_val to cint5
Add a rule how to build C-dictionaries, needed for G__c_stdfunc.c.

No rootmap entries for TCint - CINT should never ever try to autoload it.
It's either linked anyway or we dlopen it by hand.


git-svn-id: http://root.cern.ch/svn/root/trunk@24423 27541ba8-7e3a-0410-8455-c3a389f83636