Extract zips using background thread.

OpenRA.Mods.RA/Widgets/Delegates/GameInitDelegate.cs

@@ -223,18 +223,21 @@ namespace OpenRA.Mods.RA.Widgets.Delegates
 			p.StartInfo.UseShellExecute = false;
 			p.StartInfo.CreateNoWindow = true;
 			p.StartInfo.RedirectStandardOutput = true;
-			p.Start();
-			
+			p.Start();
 			var t = new Thread( _ =>
-			{
-				// This is wrong, chrisf knows why
+			{
 				using (var reader = p.StandardOutput)
-				{
-					string s = reader.ReadLine();
-					if (string.IsNullOrEmpty(s)) continue;
+				{
+					// This is wrong, chrisf knows why
+					while (!p.HasExited)
+					{
+						string s = reader.ReadLine();
+						if (string.IsNullOrEmpty(s)) continue;
+						parseOutput(s);
 					}
-				}
-			}
+				}
+				onComplete();
+			}) { IsBackground = true };
 			t.Start();
 		}