Ensures cross compatibility for zsh and bash.
Ensures cross compatibility for zsh and bash.

Fixes bug #1207853

Change-Id: I8ab3959ac8dbb5bb199e325bfdfdc513b4327410

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