Load RATDB folder from macro

There are functions in rat to load specific ratdb files as well as folders of ratdb files; however, only the single file method is exposed to the Messenger. Would be nice to have the LoadAll function exposed as well to load whole configurations (folders).

https://github.com/AIT-WATCHMAN/rat-pac/blob/master/src/db/include/RAT/DB.hh#L203
