* Turning off default Qt support. Restricting Qt version to <= 4.9 else geant4 won't build
* Making vecgeom optional
* Differentiating between cxx11 and cxx14 support
* Making vecgeom optional. Part 2. forgot to move usolids option
* Adding explicit CXX11 and CXX14 support
* Adding more clhep version to support newer GEANT4 versions
* Adding GEANT4 versions 10.03.p03 and 10.04
* Checkpoint. Adding opengl and x11 variant. Lead up to more changes to enable X11 support
* Adding dependency on fixesproto for newer versions
* Making the X11 dependent pieces work without requiring X11 on the system
* Adding motif
* Add universal build_type variant to CMakePackage
* Override build_type in some packages with different possible values
* Remove reference to no longer existent debug variant
* Update CBTF packages with new build_type variant
* Keep note on build size of LLVM
* Initial work on flag trapping using functions called <flag>_handler and default_flag_handler
* Update packages so they do not obliterate flags
* Added append to EnvironmentModifications class
* changed EnvironmentModifications to have append_flags method
* changed flag_val to be a tuple
* Increased test coverage
* added documentation of flag handling
* Change path to CMakeLists.txt to be relative to root, not pwd
* Changes requested during code review
* Revert back to old naming of root_cmakelists_dir
* Make relative directory more clear in docs
* Revert change causing build_type AttributeError
* Fix forgotten abs_path var
* Update CLHEP with new relative path
* Update more packages with new root_cmakelists_dir syntax
