Support option for Keystone PKIZ token provider
Support option for Keystone PKIZ token provider

Keystone added support for a compressed token provider, PKIZ. This
change adds support to devstack. Set the KEYSTONE_TOKEN_FORMAT
option to "PKIZ" to configure Keystone to use it.

Change-Id: I123eef661c85cc805e950f1179b48e885078d40f

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