Patch #930307, really exit if wrong python on the mac

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@27143 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

wxPython/src/_app_ex.py

@@ -133,6 +133,8 @@ This program needs access to the screen. Please run with 'pythonw',
 not 'python', and only when you are logged in on the main display of
 your Mac."""
                     _sys.exit(1)
+            except SystemExit:
+                raise
             except:
                 pass