remove outdated comment

upstream bug was fixed long before the grizzly release

Change-Id: I23e8bbfc4f53a658717279ea2cb9add83e3db11e
make LDAP attributes configurable

Change-Id: I91b9da4cf0305e6b30e82e260533d48843332cf1
remove unused keystone_plugin.py file

Change-Id: I5aa27be1489e6def11da0a511a24a880252c6f4d
Merge "make LDAP attributes configurable"