Should fix several RetroAchievements-related isssues that were plaguing 1.9.13.
CHEEVOS: Fix need-to-activate achievement logic for non-hardcore
CHEEVOS: Don't queue rewind re-init if already on main thread
CHEEVOS: Ignore unofficial achievements unless setting is enabled
VIDEO/ROTATION: Always return false if rotation can't occur. RETRO_ENVIRONMENT_SET_ROTATION should return false when rotation has been forcefully disabled in frontend, that way the core can decide if aspect ratio should be rotated or not for vertical games. Useful for FBNeo for instance.