Finish the osx packaging script

packaging/osx/OpenRA.app/Contents/MacOS/OpenRA

@@ -0,0 +1,8 @@
+#!/bin/sh
+# Application-launcher for OpenRA.
+# Executes the game binary inside the ../Resources directory with the correct working directory
+# Based on the file generated by the mono mkbundle utility
+
+APP_PATH=`echo $0 | awk '{split($0,patharr,"/"); idx=1; while(patharr[idx+3] != "") { if (patharr[idx] != "/") {printf("%s/", patharr[idx]); idx++ }} }'`
+cd "$APP_PATH/Contents/Resources"
+./OpenRA