[MERGE] Handle groups more gracefully in Django

[Stephen Gallagher]

This supersedes the patch I sent earlier today.

I tested this by manually modifying the user database and confirming 
that FAS overrode all settings I made locally, either removing or adding 
group memberships as appropriate.

When the groups are unchanged, we will only require a single lookup into 
the database, as opposed to one per group the user was a member of.

It also addresses a bug where users whose group membership was revoked 
would still appear to be a member within Django apps.

-- 
Stephen Gallagher
RHCE 804006346421761

Delivering value year after year.
Red Hat ranks #1 in value among software vendors.
http://www.redhat.com/promo/vendor/
-------------- next part --------------
A non-text attachment was scrubbed...
Name: python-fedora-628.patch
Type: text/x-patch
Size: 4178 bytes
Desc: not available
Url : http://lists.fedoraproject.org/pipermail/infrastructure/attachments/20100419/ff5bca26/attachment.bin