[1.3.X] Fixed `LayerMapping` to support `BigIntegerField`.

Backport of r15961 from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.3.X@15962 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/contrib/gis/utils/layermapping.py

@@ -57,6 +57,7 @@ class LayerMapping(object):
         # This is a reminder that XMLField is deprecated
         # and this needs to be removed in 1.4
         models.XMLField : OFTString,
+        models.BigIntegerField : (OFTInteger, OFTReal, OFTString),
         models.SmallIntegerField : (OFTInteger, OFTReal, OFTString),
         models.PositiveSmallIntegerField : (OFTInteger, OFTReal, OFTString),
         }