Rework decoration renderable traits:

- Removed implicit pip definitions and IPips interface.
  New decoration traits have been added to render them.
  Pip types are no longer hardcoded in OpenRA.Game.

- Decoration rendering is now managed by SelectionDecorations(Base),
  which allows us to remove assumptions about the selection box
  geometry from the decoration traits.

- RenderNameTag has been replaced by WithNameTagDecoration, which is
  an otherwise normal decoration trait.

- Unify the configuration and reduce duplication between traits.

- Removed hardcoded references to specific selection box renderables.

- Remove legacy cruft.

OpenRA.Mods.Common/UpdateRules/UpdatePath.cs

@@ -61,9 +61,8 @@ namespace OpenRA.Mods.Common.UpdateRules
 				new ReplaceAttackTypeStrafe()
 			}),
 
-			new UpdatePath("release-20200202", new UpdateRule[]
+			new UpdatePath("release-20200202", "playtest-20200303", new UpdateRule[]
 			{
-				// Bleed only changes here
 				new RemoveYesNo(),
 				new RemoveInitialFacingHardcoding(),
 				new RemoveAirdropActorTypeDefault(),
@@ -74,6 +73,13 @@ namespace OpenRA.Mods.Common.UpdateRules
 				new RenameSpins(),
 				new CreateScreenShakeWarhead(),
 				new RenameRallyPointPath(),
+			}),
+
+			new UpdatePath("playtest-20200303", new UpdateRule[]
+			{
+				// Bleed only changes here
+				new AddPipDecorationTraits(),
+				new ModernizeDecorationTraits(),
 			})
 		};