Added Project Balance compatibility patch

This patch is almost completely functional, the main problem right now is that the expanded legacy of rome mechanics must be redone for project balance and I'm still figuring out how to properly override the pb and acr files in the .mod file.

Other problems that I believe are related to the .mod file not having been set up properly yet is religions being doubled in the game and flags being all messed up.

I wasn't sure how to send this to a non existing branch that would be called wip-pb-patch so I just sent it to the master.