Fix configure to metadata_agent.ini
Fix configure to metadata_agent.ini

Devstack set auth_uri to metadata_agent.ini in _neutron_setup_keystone function.
But Metadata_agent use auth_url not auth_uri.

This is regression caused by https://review.openstack.org/#/c/122882/

Change-Id: Iac8f240558abcdc5bcee3d3c87cef5ad3bb007e8
Closes-bug: #1373859

ozamiatin/devstack,prithivm/branch01,TwinkleChawla/devstack,ozamiatin/devstack,sc68cal/devstack,liuquansheng47/devstack,affo/devstack,bljgaurav/openstack-test,LoHChina/devstack,dtroyer/devstack,avvocatodemarchis/devstack,upadhyay-prashant/devstack,Mahito/devstack,costingalan/devstack,mssumanth/devstack,prithivm/branch01,nuxeh/devstack,pczerkas/devstack,pczerkas/devstack,pacinete/devstack,flavio-fernandes/devstack,LoHChina/devstack,mmasaki/devstack,mc2014/devstack,bigswitch/devstack,BSJAIN92/OpenStack,mmasaki/devstack,andrewrothstein/devstack,thomasem/devstack,bljgaurav/openstack-test,bigswitch/devstack,sc68cal/devstack,bq-xiao/devstack,pombredanne/devstack,wenhuizhang/devstack,vishnugonela/devstack,NaokiMiyata/devstack,j4/devstack,kplus/devstack-moonshot,olivierlemasle/devstack,samgoon/devstack,sequenceiq/devstack,HPCHub/devstack,CloudServer/devstack,olivierlemasle/devstack,andrewrothstein/devstack,vsham20/devstack,noironetworks/devstack,vishnugonela/devstack,thomasem/devstack,group-policy/devstack,avvocatodemarchis/devstack,BSJAIN92/OpenStack,dtroyer/devstack,eharney/devstack,atulpatil301/devstack,richliu/devstack,herrsechs/devstack,eharney/devstack,liuquansheng47/devstack,NaokiMiyata/devstack,CloudServer/devstack,nawawi/openstack,promptworks/devstack,HPCHub/devstack,dirkmueller/devstack,sequenceiq/devstack,TwinkleChawla/devstack,neerja28/Devstack_GlusterFS,bq-xiao/devstack,parul24/devstack,wenhuizhang/devstack,kplus/devstack-moonshot,flavio-fernandes/devstack,mssumanth/devstack,j4/devstack,rushiagr/devstack,neerja28/Devstack_GlusterFS,rushiagr/devstack,pombredanne/devstack,herrsechs/devstack,varunarya10/devstack,group-policy/devstack,parul24/devstack,nuxeh/devstack,Mahito/devstack,noironetworks/devstack,promptworks/devstack,costingalan/devstack,affo/devstack,bswartz/devstack,pacinete/devstack,dirkmueller/devstack,upadhyay-prashant/devstack,nawawi/openstack,openstack-dev/devstack,varunarya10/devstack,openstack-dev/devstack,richliu/devstack,vsham20/devstack,atulpatil301/devstack,bswartz/devstack,mc2014/devstack,samgoon/devstack