Add missing config option os_auth_url
Add missing config option os_auth_url

Without this option will appear as an error:
Skip interval_task because Keystone error:
Authorization Failed: Unable to establish connection to
http://localhost:5000/v2.0/tokens

Closes-Bug: #1325383

Change-Id: I42fe92596d9d475f2c5b2a6aa6b49d2b7b821c54

sequenceiq/devstack,Mahito/devstack,mc2014/devstack,mmasaki/devstack,openstack-dev/devstack,costingalan/devstack,NaokiMiyata/devstack,sc68cal/devstack,dirkmueller/devstack,bswartz/devstack,nawawi/openstack,vishnugonela/devstack,atulpatil301/devstack,openstack-dev/devstack,varunarya10/devstack,herrsechs/devstack,parul24/devstack,group-policy/devstack,bljgaurav/openstack-test,pczerkas/devstack,eharney/devstack,atulpatil301/devstack,affo/devstack,ozamiatin/devstack,prithivm/branch01,samgoon/devstack,sequenceiq/devstack,promptworks/devstack,olivierlemasle/devstack,samgoon/devstack,bswartz/devstack,flavio-fernandes/devstack,sc68cal/devstack,virtualopensystems/devstack,CloudServer/devstack,LoHChina/devstack,prithivm/branch01,CloudServer/devstack,herrsechs/devstack,bljgaurav/openstack-test,pacinete/devstack,olivierlemasle/devstack,nuxeh/devstack,tianweizhang/devstack,promptworks/devstack,tianweizhang/devstack,TwinkleChawla/devstack,eshnil2000/devstack,bigswitch/devstack,andrewrothstein/devstack,kplus/devstack-moonshot,avvocatodemarchis/devstack,vsham20/devstack,mssumanth/devstack,pombredanne/devstack,dtroyer/devstack,andrewrothstein/devstack,BSJAIN92/OpenStack,TwinkleChawla/devstack,j4/devstack,mmasaki/devstack,HPCHub/devstack,wenhuizhang/devstack,upadhyay-prashant/devstack,wenhuizhang/devstack,dtroyer/devstack,group-policy/devstack,ozamiatin/devstack,j4/devstack,Mahito/devstack,upadhyay-prashant/devstack,varunarya10/devstack,HPCHub/devstack,mssumanth/devstack,liuquansheng47/devstack,liuquansheng47/devstack,pombredanne/devstack,dirkmueller/devstack,richliu/devstack,rushiagr/devstack,neerja28/Devstack_GlusterFS,affo/devstack,avvocatodemarchis/devstack,rushiagr/devstack,bq-xiao/devstack,innodee/openstackk,kplus/devstack-moonshot,LoHChina/devstack,flavio-fernandes/devstack,bigswitch/devstack,thomasem/devstack,pacinete/devstack,parul24/devstack,eharney/devstack,nawawi/openstack,neerja28/Devstack_GlusterFS,NaokiMiyata/devstack,BSJAIN92/OpenStack,noironetworks/devstack,vishnugonela/devstack,nuxeh/devstack,costingalan/devstack,pczerkas/devstack,bq-xiao/devstack,noironetworks/devstack,thomasem/devstack,mc2014/devstack,vsham20/devstack,richliu/devstack