[1.1.X] Fixed #4140: Documented the ORA-06552 error that can occur when a...

[1.1.X] Fixed #4140: Documented the ORA-06552 error that can occur when a keyword is used as a field name in the Oracle notes.  Backport of r12346 from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.1.X@12347 bcc190cf-cafb-0310-a4f2-bffc1f526a37