Overhaul target line rendering:

- Targets are now defined by the activities
- Queued activities are shown
- Support custom attack colors

OpenRA.Mods.Common/Traits/Buildings/RallyPoint.cs

@@ -21,6 +21,9 @@ namespace OpenRA.Mods.Common.Traits
 	{
 		public readonly string Image = "rallypoint";
 
+		[Desc("Width (in pixels) of the rallypoint line.")]
+		public readonly int LineWidth = 2;
+
 		[SequenceReference("Image")]
 		public readonly string FlagSequence = "flag";