Correct docstring for common.authorization
Correct docstring for common.authorization

The docstring for the common.authorization module was incomplete
because it was missing several fields that are put into the
auth context dict.

Change-Id: Ib60cfd9989d55f2be3faa122728431ca93a98813

roopali8/keystone,ajayaa/keystone,rajalokan/keystone,dims/keystone,himanshu-setia/keystone,dims/keystone,mahak/keystone,cernops/keystone,rajalokan/keystone,himanshu-setia/keystone,klmitch/keystone,openstack/keystone,openstack/keystone,ilay09/keystone,maestro-hybrid-cloud/keystone,rajalokan/keystone,ilay09/keystone,openstack/keystone,cernops/keystone,klmitch/keystone,takeshineshiro/keystone,mahak/keystone,mahak/keystone,maestro-hybrid-cloud/keystone,takeshineshiro/keystone,idjaw/keystone,ilay09/keystone,roopali8/keystone,ajayaa/keystone,idjaw/keystone