Added check to verify email exists when filtering users.
Added check to verify email exists when filtering users.

  * fixes bug 953809

Change-Id: Ib43c404bfc12ec4f6a0c8e47792fad01d1aaeec6

idjaw/horizon,gerrive/horizon,mandeepdhami/horizon,idjaw/horizon,vladryk/horizon,openstack-ja/horizon,mdavid/horizon,yanheven/console,eayunstack/horizon,Tesora/tesora-horizon,NCI-Cloud/horizon,tqtran7/horizon,sandvine/horizon,dan1/horizon-x509,damien-dg/horizon,xinwu/horizon,mrunge/horizon_lib,endorphinl/horizon,netscaler/horizon,mdavid/horizon,agileblaze/OpenStackTwoFactorAuthentication,redhat-cip/horizon,kaiweifan/horizon,j4/horizon,xinwu/horizon,rickerc/horizon_audit,zouyapeng/horizon,Metaswitch/horizon,tanglei528/horizon,NCI-Cloud/horizon,doug-fish/horizon,aaronorosen/horizon-congress,django-leonardo/horizon,doug-fish/horizon,vbannai/disk-qos-horizon,1ukash/horizon,gerrive/horizon,NeCTAR-RC/horizon,orbitfp7/horizon,Metaswitch/horizon,dan1/horizon-proto,icloudrnd/automation_tools,redhat-openstack/horizon,asomya/test,gerrive/horizon,watonyweng/horizon,rdo-management/tuskar-ui,orbitfp7/horizon,JioCloud/horizon,flochaz/horizon,liyitest/rr,Metaswitch/horizon,saydulk/horizon,flochaz/horizon,promptworks/horizon,FNST-OpenStack/horizon,redhat-openstack/horizon,xme1226/horizon,ikargis/horizon_fod,yjxtogo/horizon,JioCloud/horizon,gerrive/horizon,yeming233/horizon,xme1226/horizon,philoniare/horizon,newrocknj/horizon,Mirantis/mos-horizon,rdo-management/tuskar-ui,wolverineav/horizon,rdo-management/tuskar-ui,citrix-openstack-build/horizon,FNST-OpenStack/horizon,1ukash/horizon,anthonydillon/horizon,django-leonardo/horizon,kfox1111/horizon,coreycb/horizon,Daniex/horizon,Metaswitch/horizon,endorphinl/horizon,orbitfp7/horizon,savi-dev/horizon,RudoCris/horizon,Solinea/horizon,orbitfp7/horizon,LabAdvComp/tukey_portal,j4/horizon,damien-dg/horizon,yeming233/horizon,Dark-Hacker/horizon,bigswitch/horizon,icloudrnd/automation_tools,nvoron23/avos,Daniex/horizon,endorphinl/horizon-fork,Dark-Hacker/horizon,davidcusatis/horizon,dan1/horizon-proto,RudoCris/horizon,vbannai/disk-qos-horizon,Hodorable/0602,VaneCloud/horizon,CiscoSystems/horizon,pranavtendolkr/horizon,kfox1111/horizon,bigswitch/horizon,netscaler/horizon,endorphinl/horizon,django-leonardo/horizon,spring-week-topos/horizon-week,CiscoSystems/avos,anthonydillon/horizon,Frostman/eho-horizon,davidcusatis/horizon,sandvine/horizon,redhat-cip/horizon,Tesora/tesora-horizon,gochist/horizon,bac/horizon,promptworks/horizon,bac/horizon,maestro-hybrid-cloud/horizon,Dark-Hacker/horizon,karthik-suresh/horizon,kaiweifan/horizon,doug-fish/horizon,endorphinl/horizon,RudoCris/horizon,eayunstack/horizon,dan1/horizon-x509,henaras/horizon,henaras/horizon,openstack/horizon,ging/horizon,newrocknj/horizon,mrunge/horizon_lib,vbannai/disk-qos-horizon,opencloudconsortium/tukey-portal,Solinea/horizon,bac/horizon,django-leonardo/horizon,mdavid/horizon,coreycb/horizon,philoniare/horizon,FNST-OpenStack/horizon,blueboxgroup/horizon,Frostman/eho-horizon,NeCTAR-RC/horizon,newrocknj/horizon,Daniex/horizon,damien-dg/horizon,JioCloud/horizon,bigswitch/horizon,NeCTAR-RC/horizon,Tesora/tesora-horizon,coreycb/horizon,liyitest/rr,Solinea/horizon,takeshineshiro/horizon,doug-fish/horizon,openstack/horizon,tanglei528/horizon,wangxiangyu/horizon,Hodorable/0602,ChameleonCloud/horizon,newrocknj/horizon,nvoron23/avos,sandvine/horizon,noironetworks/horizon,Mirantis/mos-horizon,zouyapeng/horizon,CiscoSystems/horizon,tellesnobrega/horizon,promptworks/horizon,watonyweng/horizon,vladryk/horizon,tsufiev/horizon,watonyweng/horizon,BiznetGIO/horizon,1ukash/horizon,Tesora/tesora-horizon,kfox1111/horizon,mrunge/openstack_horizon,dan1/horizon-proto,openstack/horizon,openstack-ja/horizon,j4/horizon,mrunge/horizon,watonyweng/horizon,froyobin/horizon,asomya/test,VaneCloud/horizon,mrunge/horizon,wolverineav/horizon,wangxiangyu/horizon,aaronorosen/horizon-congress,davidcusatis/horizon,opencloudconsortium/tukey-portal,zouyapeng/horizon,mrunge/openstack_horizon,tuskar/tuskar-ui,tellesnobrega/horizon,maestro-hybrid-cloud/horizon,blueboxgroup/horizon,flochaz/horizon,froyobin/horizon,maestro-hybrid-cloud/horizon,Hodorable/0602,yanheven/console,agileblaze/OpenStackTwoFactorAuthentication,CiscoSystems/avos,mandeepdhami/horizon,redhat-cip/horizon,karthik-suresh/horizon,j4/horizon,tuskar/tuskar-ui,agileblaze/OpenStackTwoFactorAuthentication,rickerc/horizon_audit,izadorozhna/dashboard_integration_tests,netscaler/horizon,wolverineav/horizon,Solinea/horizon,Mirantis/mos-horizon,ChameleonCloud/horizon,wangxiangyu/horizon,takeshineshiro/horizon,nvoron23/avos,luhanhan/horizon,zouyapeng/horizon,redhat-openstack/horizon,tqtran7/horizon,rickerc/horizon_audit,mdavid/horizon,idjaw/horizon,occ-data/tukey-portal,tsufiev/horizon,citrix-openstack-build/horizon,ChameleonCloud/horizon,CiscoSystems/avos,openstack-ja/horizon,tsufiev/horizon,BiznetGIO/horizon,wangxiangyu/horizon,vladryk/horizon,RudoCris/horizon,endorphinl/horizon-fork,pranavtendolkr/horizon,bigswitch/horizon,pranavtendolkr/horizon,blueboxgroup/horizon,ging/horizon,dan1/horizon-proto,asomya/test,r-icarus/openstack_microserver,mrunge/horizon_lib,henaras/horizon,sandvine/horizon,endorphinl/horizon-fork,luhanhan/horizon,tellesnobrega/horizon,99cloud/keystone_register,kaiweifan/horizon,idjaw/horizon,spring-week-topos/horizon-week,spring-week-topos/horizon-week,tanglei528/horizon,nvoron23/avos,maestro-hybrid-cloud/horizon,yjxtogo/horizon,karthik-suresh/horizon,noironetworks/horizon,noironetworks/horizon,endorphinl/horizon-fork,savi-dev/horizon,NeCTAR-RC/horizon,gochist/horizon,flochaz/horizon,philoniare/horizon,icloudrnd/automation_tools,LabAdvComp/tukey_portal,saydulk/horizon,mrunge/horizon,damien-dg/horizon,henaras/horizon,ikargis/horizon_fod,anthonydillon/horizon,aaronorosen/horizon-congress,ging/horizon,redhat-cip/horizon,CiscoSystems/horizon,pranavtendolkr/horizon,dan1/horizon-x509,gochist/horizon,xme1226/horizon,ChameleonCloud/horizon,vladryk/horizon,promptworks/horizon,Dark-Hacker/horizon,CiscoSystems/horizon,occ-data/tukey-portal,ging/horizon,philoniare/horizon,xinwu/horizon,BiznetGIO/horizon,tellesnobrega/horizon,karthik-suresh/horizon,tuskar/tuskar-ui,r-icarus/openstack_microserver,BiznetGIO/horizon,LabAdvComp/tukey_portal,froyobin/horizon,r-icarus/openstack_microserver,mandeepdhami/horizon,LabAdvComp/tukey_portal,saydulk/horizon,saydulk/horizon,liyitest/rr,mrunge/openstack_horizon,Mirantis/mos-horizon,icloudrnd/automation_tools,izadorozhna/dashboard_integration_tests,VaneCloud/horizon,takeshineshiro/horizon,wolverineav/horizon,tsufiev/horizon,NCI-Cloud/horizon,citrix-openstack-build/horizon,blueboxgroup/horizon,Daniex/horizon,liyitest/rr,rdo-management/tuskar-ui,davidcusatis/horizon,luhanhan/horizon,redhat-openstack/horizon,anthonydillon/horizon,kfox1111/horizon,xinwu/horizon,savi-dev/horizon,tqtran7/horizon,openstack/horizon,takeshineshiro/horizon,bac/horizon,occ-data/tukey-portal,opencloudconsortium/tukey-portal,ikargis/horizon_fod,99cloud/keystone_register,yeming233/horizon,VaneCloud/horizon,Frostman/eho-horizon,yjxtogo/horizon,eayunstack/horizon,99cloud/keystone_register,yeming233/horizon,CiscoSystems/avos,Hodorable/0602,yjxtogo/horizon,yanheven/console,FNST-OpenStack/horizon,mandeepdhami/horizon,NCI-Cloud/horizon,agileblaze/OpenStackTwoFactorAuthentication,dan1/horizon-x509,tqtran7/horizon,coreycb/horizon,noironetworks/horizon,luhanhan/horizon