RHS GREF Config Support

[rverdi12]

Please update RHS Config support to include the new GREF factions as well as US Naval units (I notice when ALiVE is spawning USAF units it denotes a lack of a naval category, they just added some neat naval assets).

Thanks :)

[TheMagnetar]

I am willing to take upon this if nobody has started it yet.

[DavisBrown723]

Nobody has started, have a crack at it

[DavisBrown723]

Done in most recent release.