FLP: fix include dir cache unset, allow for version.h and .hpp naming
FLP: fix include dir cache unset, allow for version.h and .hpp naming

biddisco/CMake,ptoharia/CMake,hernando/vmmlib,BlueBrain/Tuvok,jafyvilla/CMake,ptoharia/CMake,hernando/vmmlib,biddisco/CMake,rballester/vmmlib,jafyvilla/CMake,jafyvilla/CMake,ptoharia/CMake,shurikasa/CMake,BlueBrain/Tuvok,hernando/vmmlib,ptoharia/CMake,biddisco/CMake,shurikasa/CMake,shuaibarshad/KAUST-CMake,BlueBrain/Tuvok,shuaibarshad/KAUST-CMake,shuaibarshad/KAUST-CMake,jafyvilla/CMake,rballester/vmmlib,biddisco/CMake,shurikasa/CMake,tribal-tec/vmmlib,rballester/vmmlib,shuaibarshad/KAUST-CMake,shurikasa/CMake