Tag to be used with the master branch of atlas/athena.
Update(s) since 2.0.108:
  - Removed the automated setting of the PACKAGE_VERSION macro from the compilation commands;
    * At the same time added the PACKAGE macro to the build of resolveAtlasAddr2Line, which was previously silently relying on the existence of the PACKAGE_VERSION macro;
  - Added Findheaptrack.cmake to AtlasLCG;
  - Updated Acts to version v9.1.0.