Import core.* in keystone.tests
Import core.* in keystone.tests

This will allow us to 'from keystone import tests' to import core
test functions. This is consistent with other modules in Keystone.

Change-Id: I8c3044cad85fee37a237264da198465fcb3c0898

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