Back-port Nick's fix from trunk

RunAllTests only discovered files in the last seen directory.
It now discovers more, but they're broken (fix to the tests not
back-ported yet).

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/branches/maintenance/gramps34@22790 4ae1f11a-8b86-4847-b8af-ab372f36d1fd