Merge repair and rearm anim traits into WithResupplyAnimation

This is the safest approach to avoid conflicts/visual glitches when the host is responsible for both resupply types.
The new trait will simply play a looping animation as long as the actor is resupplying in any form.

OpenRA.Mods.Common/Traits/Air/Aircraft.cs

@@ -489,7 +489,7 @@ namespace OpenRA.Mods.Common.Traits
 		{
 			var name = a.Info.Name;
 			if (Info.RearmBuildings.Contains(name))
-				yield return new Rearm(self);
+				yield return new Rearm(self, a, WDist.Zero);
 
 			// The ResupplyAircraft activity guarantees that we're on the helipad
 			if (Info.RepairBuildings.Contains(name))