Add minimum release support notes for federation
Add minimum release support notes for federation

Document which releases of keystone are supported for which
federation related task.

Change-Id: Ibcd349bdb4c4c21fec6bb71bac77f9d404e84dcf

klmitch/keystone,ajayaa/keystone,jumpstarter-io/keystone,promptworks/keystone,dims/keystone,rajalokan/keystone,idjaw/keystone,mahak/keystone,vivekdhayaal/keystone,ilay09/keystone,mahak/keystone,maestro-hybrid-cloud/keystone,roopali8/keystone,openstack/keystone,dims/keystone,nuxeh/keystone,cernops/keystone,rajalokan/keystone,mahak/keystone,nuxeh/keystone,nuxeh/keystone,ilay09/keystone,promptworks/keystone,dstanek/keystone,ilay09/keystone,klmitch/keystone,maestro-hybrid-cloud/keystone,rushiagr/keystone,promptworks/keystone,jamielennox/keystone,vivekdhayaal/keystone,jamielennox/keystone,takeshineshiro/keystone,rushiagr/keystone,ajayaa/keystone,idjaw/keystone,takeshineshiro/keystone,jonnary/keystone,openstack/keystone,jumpstarter-io/keystone,openstack/keystone,dstanek/keystone,vivekdhayaal/keystone,rajalokan/keystone,jumpstarter-io/keystone,cernops/keystone,jonnary/keystone,himanshu-setia/keystone,dstanek/keystone,rushiagr/keystone,roopali8/keystone,himanshu-setia/keystone