compile GEANT4 using C++11; compile it & xerces w/ 8 threads; comment
out snoing auto-updates
change rat-dev to expect root6
Add new root6 object & RootDev class
clone my fork of rat, not the main snoplus repo
enable only the usual (subset) of root options
fix typo in GEANT4 build flag
compile root6 with C++14 & enable all options