Hide Cancel button if no cancel_url is provided
Hide Cancel button if no cancel_url is provided

If there is no cancel_url is defined on the ModalFormView
class, hide the Cancel button.

Change-Id: Id27c60525560dcfdb5cfafa2c4cd7b4edffea158
Closes-Bug: #1434548

gerrive/horizon,tellesnobrega/horizon,bac/horizon,BiznetGIO/horizon,NeCTAR-RC/horizon,ChameleonCloud/horizon,anthonydillon/horizon,saydulk/horizon,watonyweng/horizon,noironetworks/horizon,NeCTAR-RC/horizon,anthonydillon/horizon,xinwu/horizon,davidcusatis/horizon,pranavtendolkr/horizon,Dark-Hacker/horizon,redhat-cip/horizon,agileblaze/OpenStackTwoFactorAuthentication,redhat-openstack/horizon,xinwu/horizon,anthonydillon/horizon,BiznetGIO/horizon,openstack/horizon,Hodorable/0602,idjaw/horizon,dan1/horizon-x509,Solinea/horizon,endorphinl/horizon-fork,RudoCris/horizon,kfox1111/horizon,tqtran7/horizon,henaras/horizon,blueboxgroup/horizon,Dark-Hacker/horizon,redhat-openstack/horizon,watonyweng/horizon,icloudrnd/automation_tools,henaras/horizon,watonyweng/horizon,newrocknj/horizon,endorphinl/horizon,damien-dg/horizon,blueboxgroup/horizon,redhat-cip/horizon,dan1/horizon-proto,wolverineav/horizon,kfox1111/horizon,Dark-Hacker/horizon,Solinea/horizon,j4/horizon,wolverineav/horizon,Hodorable/0602,vladryk/horizon,maestro-hybrid-cloud/horizon,eayunstack/horizon,philoniare/horizon,BiznetGIO/horizon,saydulk/horizon,wolverineav/horizon,dan1/horizon-proto,Dark-Hacker/horizon,mdavid/horizon,agileblaze/OpenStackTwoFactorAuthentication,yjxtogo/horizon,Hodorable/0602,NeCTAR-RC/horizon,redhat-cip/horizon,vladryk/horizon,newrocknj/horizon,Hodorable/0602,Metaswitch/horizon,bigswitch/horizon,damien-dg/horizon,maestro-hybrid-cloud/horizon,sandvine/horizon,karthik-suresh/horizon,endorphinl/horizon,Metaswitch/horizon,takeshineshiro/horizon,vladryk/horizon,redhat-openstack/horizon,takeshineshiro/horizon,xinwu/horizon,Tesora/tesora-horizon,Mirantis/mos-horizon,dan1/horizon-proto,yjxtogo/horizon,pranavtendolkr/horizon,Mirantis/mos-horizon,watonyweng/horizon,kfox1111/horizon,karthik-suresh/horizon,bac/horizon,liyitest/rr,idjaw/horizon,anthonydillon/horizon,yjxtogo/horizon,agileblaze/OpenStackTwoFactorAuthentication,mandeepdhami/horizon,mandeepdhami/horizon,luhanhan/horizon,icloudrnd/automation_tools,Tesora/tesora-horizon,django-leonardo/horizon,Solinea/horizon,mdavid/horizon,sandvine/horizon,saydulk/horizon,xinwu/horizon,tellesnobrega/horizon,FNST-OpenStack/horizon,tellesnobrega/horizon,kfox1111/horizon,eayunstack/horizon,gerrive/horizon,saydulk/horizon,davidcusatis/horizon,philoniare/horizon,maestro-hybrid-cloud/horizon,coreycb/horizon,henaras/horizon,icloudrnd/automation_tools,mdavid/horizon,ChameleonCloud/horizon,karthik-suresh/horizon,maestro-hybrid-cloud/horizon,tellesnobrega/horizon,j4/horizon,takeshineshiro/horizon,pranavtendolkr/horizon,RudoCris/horizon,luhanhan/horizon,openstack/horizon,BiznetGIO/horizon,j4/horizon,philoniare/horizon,doug-fish/horizon,mandeepdhami/horizon,dan1/horizon-x509,agileblaze/OpenStackTwoFactorAuthentication,bigswitch/horizon,Mirantis/mos-horizon,vladryk/horizon,takeshineshiro/horizon,bac/horizon,mandeepdhami/horizon,newrocknj/horizon,FNST-OpenStack/horizon,doug-fish/horizon,newrocknj/horizon,Mirantis/mos-horizon,ChameleonCloud/horizon,davidcusatis/horizon,dan1/horizon-x509,redhat-openstack/horizon,philoniare/horizon,yeming233/horizon,tqtran7/horizon,luhanhan/horizon,Tesora/tesora-horizon,coreycb/horizon,yeming233/horizon,RudoCris/horizon,karthik-suresh/horizon,sandvine/horizon,blueboxgroup/horizon,django-leonardo/horizon,bac/horizon,ChameleonCloud/horizon,davidcusatis/horizon,Metaswitch/horizon,noironetworks/horizon,bigswitch/horizon,FNST-OpenStack/horizon,openstack/horizon,pranavtendolkr/horizon,yeming233/horizon,damien-dg/horizon,bigswitch/horizon,endorphinl/horizon-fork,coreycb/horizon,yeming233/horizon,eayunstack/horizon,dan1/horizon-proto,django-leonardo/horizon,NeCTAR-RC/horizon,idjaw/horizon,tqtran7/horizon,Metaswitch/horizon,blueboxgroup/horizon,noironetworks/horizon,noironetworks/horizon,liyitest/rr,endorphinl/horizon,mdavid/horizon,doug-fish/horizon,coreycb/horizon,gerrive/horizon,openstack/horizon,damien-dg/horizon,wolverineav/horizon,icloudrnd/automation_tools,endorphinl/horizon-fork,redhat-cip/horizon,luhanhan/horizon,gerrive/horizon,endorphinl/horizon,henaras/horizon,django-leonardo/horizon,FNST-OpenStack/horizon,sandvine/horizon,j4/horizon,Solinea/horizon,liyitest/rr,RudoCris/horizon,doug-fish/horizon,dan1/horizon-x509,endorphinl/horizon-fork,yjxtogo/horizon,tqtran7/horizon,Tesora/tesora-horizon,liyitest/rr,idjaw/horizon