Update OSX instructions for new template location

(cherry picked from commit 62051661a0fc9316ff1c539ad5376d06fe8816ff)

reference/compiling_for_osx.rst

@@ -30,13 +30,14 @@ runs without any dependencies. Executing it will bring up the project
 manager.
 
 To create an .app like in the official builds, you need to use the template
-located in ``tools/Godot.app``. Typically:
+located in ``tools/dist/osx_tools.app``. Typically (for a "fat" binary that
+supports both 32-bit and 64-bit architectures):
 
 ::
 
     user@host:~/godot$ cp -r tools/dist/osx_tools.app ./Godot.app
     user@host:~/godot$ mkdir -p Godot.app/Contents/MacOS
-    user@host:~/godot$ cp bin/godot.osx.opt.tools.64 Godot.app/Contents/MacOS/Godot
+    user@host:~/godot$ cp bin/godot.osx.opt.tools.fat Godot.app/Contents/MacOS/Godot
     user@host:~/godot$ chmod +x Godot.app/Contents/MacOS/Godot
 
 Cross-compiling