Add rhel to DISTRO match
Add rhel to DISTRO match

Match RHEL and CentOS and provide them as a DISTRO prefix of "rhel"

Change-Id: Ida19130ce9499d4d1fd2360fadc6b870b24bbc95

Mahito/devstack,deepakselvaraj/devstack,nawawi/openstack,mssumanth/devstack,bswartz/devstack,noironetworks/devstack,tianweizhang/devstack,flavio-fernandes/devstack,BSJAIN92/OpenStack,jamielennox/devstack,dtroyer/devstack,nuxeh/devstack,Yuriy-Leonov/devstack,shootstar/devstacktest,herrsechs/devstack,JioCloud/devstack,virtualopensystems/devstack,affo/devstack,affo/devstack,eharney/devstack,pczerkas/devstack,srics/devstack,Juniper/devstack,eshnil2000/devstack,dirkmueller/devstack,liuquansheng47/devstack,mssumanth/devstack,sequenceiq/devstack,BSJAIN92/OpenStack,Mahito/devstack,NaokiMiyata/devstack,andrewrothstein/devstack,avvocatodemarchis/devstack,yamt/devstack,openstack-dev/devstack,herrsechs/devstack,bljgaurav/openstack-test,noironetworks/devstack,kplus/devstack-moonshot,sc68cal/devstack,mmasaki/devstack,bq-xiao/devstack,vsham20/devstack,neerja28/Devstack_GlusterFS,tianweizhang/devstack,parul24/devstack,atulpatil301/devstack,dirkmueller/devstack,armando-migliaccio/devstack,sc68cal/devstack,ozamiatin/devstack,NaokiMiyata/devstack,pczerkas/devstack,ozamiatin/devstack,group-policy/devstack,sequenceiq/devstack,costingalan/devstack,openstack-dev/devstack,Millnert/contrail-devstack,avvocatodemarchis/devstack,innodee/openstackk,neerja28/Devstack_GlusterFS,bswartz/devstack,rushiagr/devstack,mc2014/devstack,sstrato/devstack,samgoon/devstack,olivierlemasle/devstack,mc2014/devstack,pombredanne/devstack,atulpatil301/devstack,mmasaki/devstack,wenhuizhang/devstack,olivierlemasle/devstack,nawawi/openstack,upadhyay-prashant/devstack,vishnugonela/devstack,promptworks/devstack,williamthegrey/devstack,dtroyer/devstack,thomasem/devstack,TwinkleChawla/devstack,j4/devstack,vishnugonela/devstack,pacinete/devstack,wenhuizhang/devstack,TwinkleChawla/devstack,inkerra/devstack,richliu/devstack,richliu/devstack,samgoon/devstack,LoHChina/devstack,costingalan/devstack,kplus/devstack-moonshot,eharney/devstack,flavio-fernandes/devstack,pacinete/devstack,CiscoSystems/devstack,liuquansheng47/devstack,bigswitch/devstack,bljgaurav/openstack-test,prithivm/branch01,parul24/devstack,nuxeh/devstack,rushiagr/devstack,vsham20/devstack,CloudServer/devstack,bigswitch/devstack,HPCHub/devstack,j4/devstack,varunarya10/devstack,group-policy/devstack,upadhyay-prashant/devstack,LoHChina/devstack,thomasem/devstack,andrewrothstein/devstack,HPCHub/devstack,CloudServer/devstack,varunarya10/devstack,bq-xiao/devstack,prithivm/branch01,pombredanne/devstack,promptworks/devstack