Fixed #10159 -- `F()` expressions now work on geographic fields. The tests...

Fixed #10159 -- `F()` expressions now work on geographic fields.  The tests are in `relatedapp`, which has been retrofitted to work with Oracle (minus the prior offending tests).  I'm back.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@9963 bcc190cf-cafb-0310-a4f2-bffc1f526a37