This can't replace the official release script yet as not everybody uses git
but they are much more convenient to use than the old ones for me and also
faster so I'm adding them to svn in case they can be useful to others.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@64998 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
