Fix distribution link in documentation
Fix distribution link in documentation

Fix broken link to distributions of OpenStack

Closes-Bug: #1469433
Change-Id: Ica572e11c0dedfe0684fad1c4d48b248f7003d47

Mahito/devstack,TwinkleChawla/devstack,pczerkas/devstack,vsham20/devstack,openstack-dev/devstack,dirkmueller/devstack,parul24/devstack,richliu/devstack,prithivm/branch01,wenhuizhang/devstack,HPCHub/devstack,bswartz/devstack,noironetworks/devstack,wenhuizhang/devstack,noironetworks/devstack,olivierlemasle/devstack,flavio-fernandes/devstack,pombredanne/devstack,pombredanne/devstack,pacinete/devstack,vishnugonela/devstack,LoHChina/devstack,thomasem/devstack,liuquansheng47/devstack,LoHChina/devstack,group-policy/devstack,herrsechs/devstack,pczerkas/devstack,bigswitch/devstack,mc2014/devstack,TwinkleChawla/devstack,atulpatil301/devstack,j4/devstack,upadhyay-prashant/devstack,olivierlemasle/devstack,varunarya10/devstack,vishnugonela/devstack,HPCHub/devstack,group-policy/devstack,ozamiatin/devstack,bigswitch/devstack,NaokiMiyata/devstack,herrsechs/devstack,mmasaki/devstack,mssumanth/devstack,avvocatodemarchis/devstack,prithivm/branch01,thomasem/devstack,vsham20/devstack,richliu/devstack,pacinete/devstack,flavio-fernandes/devstack,dtroyer/devstack,avvocatodemarchis/devstack,ozamiatin/devstack,upadhyay-prashant/devstack,mmasaki/devstack,liuquansheng47/devstack,dtroyer/devstack,mssumanth/devstack,bq-xiao/devstack,mc2014/devstack,nawawi/openstack,atulpatil301/devstack,bq-xiao/devstack,costingalan/devstack,eharney/devstack,samgoon/devstack,dirkmueller/devstack,j4/devstack,NaokiMiyata/devstack,parul24/devstack,nawawi/openstack,openstack-dev/devstack,Mahito/devstack,costingalan/devstack,samgoon/devstack,bswartz/devstack,varunarya10/devstack,eharney/devstack