Scrap CustomEnv library

This mod now requires mod loader PR 215. itb-community/ITB-ModLoader#215

There were some bugs that, in order to fix them, would require overriding the mod loader's altered Mission.ApplyEnvironmentEffect. This library would then need to include the mod loader's event dispatch code to not ruin it. At that point, it seems to make more sense to add the custom environment features directly to the mod loader, instead of adding layers upon layers of hacks. (Mod loader upon vanilla game, and this library upon the mod loader)

mods/custom_environment_weapon/scripts/init.lua

@@ -9,7 +9,7 @@ local mod =  {
 }
 
 function mod:init(options)
-	require(self.scriptPath.."libs/CustomEnv")
+	-- require(self.scriptPath.."libs/CustomEnv")
 	require(self.scriptPath.."env_weapon")
 end