Raise keystone.exception for HTTP 401 (bug 962563)
Raise keystone.exception for HTTP 401 (bug 962563)

Change-Id: I22e3b6769c69ef5917028980007d3295fed99fb7

takeshineshiro/keystone,rickerc/keystone_audit,takeshineshiro/keystone,rodrigods/keystone,JioCloud/keystone,ilay09/keystone,reeshupatel/demo,nuxeh/keystone,derekchiang/keystone,cloudbau/keystone,dims/keystone,openstack/keystone,jumpstarter-io/keystone,himanshu-setia/keystone,himanshu-setia/keystone,promptworks/keystone,vivekdhayaal/keystone,jamielennox/keystone,JioCloud/keystone,nuxeh/keystone,citrix-openstack-build/keystone,rickerc/keystone_audit,mahak/keystone,ntt-sic/keystone,dstanek/keystone,dstanek/keystone,dsiddharth/access-keys,openstack/keystone,ntt-sic/keystone,rickerc/keystone_audit,ilay09/keystone,savi-dev/keystone,kwss/keystone,derekchiang/keystone,cernops/keystone,townbull/keystone-dtrust,mahak/keystone,ging/keystone,roopali8/keystone,ntt-sic/keystone,rushiagr/keystone,kwss/keystone,savi-dev/keystone,ajayaa/keystone,rajalokan/keystone,idjaw/keystone,UTSA-ICS/keystone-kerberos,dims/keystone,reeshupatel/demo,rodrigods/keystone,cbrucks/Federated_Keystone,UTSA-ICS/keystone-kerberos,jonnary/keystone,ilay09/keystone,dstanek/keystone,citrix-openstack-build/keystone,savi-dev/keystone,jonnary/keystone,cbrucks/Federated_Keystone,cloudbau/keystone,ajayaa/keystone,cbrucks/Federated_Keystone,rajalokan/keystone,citrix-openstack-build/keystone,promptworks/keystone,nuxeh/keystone,dsiddharth/access-keys,rushiagr/keystone,jamielennox/keystone,openstack/keystone,townbull/keystone-dtrust,vivekdhayaal/keystone,roopali8/keystone,maestro-hybrid-cloud/keystone,promptworks/keystone,kwss/keystone,maestro-hybrid-cloud/keystone,jumpstarter-io/keystone,dsiddharth/access-keys,rushiagr/keystone,jumpstarter-io/keystone,blueboxgroup/keystone,vivekdhayaal/keystone,reeshupatel/demo,MaheshIBM/keystone,blueboxgroup/keystone,townbull/keystone-dtrust,derekchiang/keystone,klmitch/keystone,ging/keystone,cloudbau/keystone,idjaw/keystone,klmitch/keystone,cernops/keystone,mahak/keystone,MaheshIBM/keystone,rajalokan/keystone