ClonesProductionUnits:

string[] CloneableTypes	checks Cloneable.Types

Cloneable:
	string[] Types checked by ClonesProductionUnits.CloneableTypes

Added INotifyOtherProduction
	for notifying self when another actor
	produces a unit.

OpenRA.Mods.RA/OpenRA.Mods.RA.csproj

@@ -528,6 +528,8 @@
     <Compile Include="Graphics\TextRenderable.cs" />
     <Compile Include="Graphics\VoxelRenderable.cs" />
     <Compile Include="Air\FlyAwayOnIdle.cs" />
+    <Compile Include="Buildings\ClonesProducedUnits.cs" />
+    <Compile Include="Cloneable.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\OpenRA.Game\OpenRA.Game.csproj">