Install a platform-specific configuration file including details
about the linker and component libraries of the project.

Improved the platform-independent configuration file to present
the right variables (<project>_LIBRARY_DIRS etc.)

Note that LCG_PREFIX_PATH is cached so it will not be recomputed.

Use the special function "require" to declare the subdirectories
that need to be processed first.

This makes them closer to the standard implementations.

The Debian versions include a bugfix that allows
the explicit selection of the version of Python
(the standard ones pick up the latest).

Switched to a model where LCG versions of the libraries can be found
by the standard CMake FindXYZ.cmake modules.

Few contributed modules have still to be upgraded to generic.

* master: (64 commits)
  Updated tag_release.py script to allow tagging from a (global) branch.
  forgot to update Gaudi/cmt/version.cmt
  Preparing release of Gaudi v22r2
  Fixed a defect spotted by Coverity in KeyedObject (UNINIT_CTOR).
  Fixed a defect spotted by Coverity in KeyedObject (UNINIT_CTOR).
  Added use of LIKELY/UNLIKELY for testing.
  Moved the LIKELY and UNLIKELY macros to GaudiKernel/Kernel.h
  Merged changes for branch prediction helper macros (LIKELY/UNLIKELY) https://svnweb.cern.ch/trac/gaudi/changeset/6471
  Fixed the usage of cpp fragments on Windows.
  Fixed a bug introduced with revision 6509. (d4ddd261)
  Restored fix to Makefile.cmt lost when merging GAUDI_nativedep. (fix was in 581f984c)
  fixed permissions of EventNodeKiller.{h,cpp}
  Patch #4814: Move EventNodeKiller algorithm from LHCb to Gaudi. Imported EventNodeKiller.{h,cpp} from   svn+ssh://svn.cern.ch/reps/lhcb/LHCb/trunk/Kernel/LHCbAlgs/src Modified the imported files to avoid generating debug messages if they are not going to be printed. https://savannah.cern.ch/patch/?4814
  Updated GaudiSvc release notes (patch #4819).
  Applied patch #4819 (part 2)
  Applied patch #4819 (part 1)
  Updated GaudiPolicy release notes.
  Fixed bug #79627: ChronoAuditor broken for custom event types https://savannah.cern.ch/bugs/?79627
  Fixed a typo
  Fixed a couple of warnings coming from NDEBUG.
  ...

git-svn-id: svn+ssh://svn.cern.ch/reps/gaudi/Gaudi/trunk@6538 53ecefc3-a64d-0410-9bdf-b8581fa3287e