Added filter for Gimp that will group up biomes.
Added filter for Gimp that will group up biomes.

esampson/worldengine,psi29a/worldengine,psi29a/worldengine,tmfoltz/worldengine,Mindwerks/worldengine,MM1nd/worldengine,MM1nd/worldengine,esampson/worldengine,Mindwerks/worldengine,tmfoltz/worldengine