Lcg 81b aarch64
Merge request for 81b aarch64 build to sft/lcgcmake arm_tests branch. Main changes: updating config.guess scripts before building package. heptools-81b.cmake toolchain has Aarch64 catches. Various adjustments to CMakeLists.txt files, shouldn't interfere if not Aarch64. Some patches introduced: GPerftools, mysql (maybe some others?) Building qt4.8.6 instead of 4.8.4 Skipping over gridexternals