Improve virt/disk/mount/nbd test coverage.
Improve virt/disk/mount/nbd test coverage.

Change-Id: I7d1c413b7a492c078ae10c840c4c20f8cf69d6a5

leilihh/novaha,apporc/nova,blueboxgroup/nova,alexandrucoman/vbox-nova-driver,CiscoSystems/nova,takeshineshiro/nova,Juniper/nova,yosshy/nova,ewindisch/nova,angdraug/nova,jeffrey4l/nova,CCI-MOC/nova,bclau/nova,double12gzh/nova,JioCloud/nova,maelnor/nova,whitepages/nova,klmitch/nova,badock/nova,CloudServer/nova,mikalstill/nova,mahak/nova,rrader/nova-docker-plugin,JianyuWang/nova,houshengbo/nova_vmware_compute_driver,DirectXMan12/nova-hacking,eharney/nova,tudorvio/nova,Stavitsky/nova,bclau/nova,devendermishrajio/nova,fnordahl/nova,devendermishrajio/nova,BeyondTheClouds/nova,adelina-t/nova,phenoxim/nova,maheshp/novatest,MountainWei/nova,phenoxim/nova,ntt-sic/nova,devoid/nova,TwinkleChawla/nova,orbitfp7/nova,alaski/nova,aristanetworks/arista-ovs-nova,Juniper/nova,hanlind/nova,spring-week-topos/nova-week,Juniper/nova,petrutlucian94/nova_dev,shootstar/novatest,cloudbau/nova,angdraug/nova,fajoy/nova,cyx1231st/nova,Yuriy-Leonov/nova,mgagne/nova,nikesh-mahalka/nova,imsplitbit/nova,vmturbo/nova,MountainWei/nova,mmnelemane/nova,virtualopensystems/nova,tangfeixiong/nova,Francis-Liu/animated-broccoli,varunarya10/nova_test_latest,sridevikoushik31/nova,silenceli/nova,rajalokan/nova,SUSE-Cloud/nova,adelina-t/nova,belmiromoreira/nova,jeffrey4l/nova,alaski/nova,mahak/nova,yatinkumbhare/openstack-nova,mahak/nova,jianghuaw/nova,NeCTAR-RC/nova,akash1808/nova_test_latest,devoid/nova,j-carpentier/nova,TieWei/nova,DirectXMan12/nova-hacking,Triv90/Nova,Metaswitch/calico-nova,viggates/nova,DirectXMan12/nova-hacking,openstack/nova,OpenAcademy-OpenStack/nova-scheduler,whitepages/nova,shahar-stratoscale/nova,eharney/nova,qwefi/nova,zhimin711/nova,virtualopensystems/nova,spring-week-topos/nova-week,openstack/nova,CloudServer/nova,rajalokan/nova,joker946/nova,LoHChina/nova,maelnor/nova,CEG-FYP-OpenStack/scheduler,watonyweng/nova,cloudbase/nova-virtualbox,TieWei/nova,petrutlucian94/nova_dev,felixma/nova,Tehsmash/nova,mandeepdhami/nova,felixma/nova,JioCloud/nova,thomasem/nova,rickerc/nova_audit,citrix-openstack-build/nova,rahulunair/nova,rajalokan/nova,ruslanloman/nova,CiscoSystems/nova,imsplitbit/nova,tianweizhang/nova,redhat-openstack/nova,saleemjaveds/https-github.com-openstack-nova,j-carpentier/nova,bigswitch/nova,watonyweng/nova,gooddata/openstack-nova,dstroppa/openstack-smartos-nova-grizzly,vladikr/nova_drafts,vmturbo/nova,shail2810/nova,sebrandon1/nova,scripnichenko/nova,citrix-openstack-build/nova,gooddata/openstack-nova,TwinkleChawla/nova,vladikr/nova_drafts,yatinkumbhare/openstack-nova,bgxavier/nova,tealover/nova,belmiromoreira/nova,iuliat/nova,aristanetworks/arista-ovs-nova,eonpatapon/nova,leilihh/nova,Yusuke1987/openstack_template,tangfeixiong/nova,Yusuke1987/openstack_template,iuliat/nova,fajoy/nova,cloudbau/nova,sridevikoushik31/nova,silenceli/nova,LoHChina/nova,Juniper/nova,berrange/nova,houshengbo/nova_vmware_compute_driver,alvarolopez/nova,takeshineshiro/nova,petrutlucian94/nova,sebrandon1/nova,BeyondTheClouds/nova,gooddata/openstack-nova,gooddata/openstack-nova,ted-gould/nova,tanglei528/nova,edulramirez/nova,cernops/nova,Triv90/Nova,barnsnake351/nova,mikalstill/nova,projectcalico/calico-nova,rajalokan/nova,eayunstack/nova,yrobla/nova,orbitfp7/nova,luogangyi/bcec-nova,cernops/nova,Tehsmash/nova,kimjaejoong/nova,raildo/nova,raildo/nova,dstroppa/openstack-smartos-nova-grizzly,jianghuaw/nova,Brocade-OpenSource/OpenStack-DNRM-Nova,affo/nova,ruslanloman/nova,yrobla/nova,viggates/nova,noironetworks/nova,zzicewind/nova,tealover/nova,zaina/nova,shahar-stratoscale/nova,Metaswitch/calico-nova,yosshy/nova,gspilio/nova,qwefi/nova,alvarolopez/nova,dawnpower/nova,sridevikoushik31/openstack,maheshp/novatest,double12gzh/nova,jianghuaw/nova,edulramirez/nova,bgxavier/nova,akash1808/nova,shail2810/nova,vmturbo/nova,sridevikoushik31/nova,cloudbase/nova-virtualbox,houshengbo/nova_vmware_compute_driver,JioCloud/nova_test_latest,sridevikoushik31/openstack,scripnichenko/nova,berrange/nova,bigswitch/nova,tianweizhang/nova,ntt-sic/nova,dawnpower/nova,SUSE-Cloud/nova,eayunstack/nova,barnsnake351/nova,nikesh-mahalka/nova,projectcalico/calico-nova,rrader/nova-docker-plugin,mmnelemane/nova,rahulunair/nova,dims/nova,jianghuaw/nova,varunarya10/nova_test_latest,Francis-Liu/animated-broccoli,hanlind/nova,isyippee/nova,plumgrid/plumgrid-nova,sridevikoushik31/nova,klmitch/nova,redhat-openstack/nova,sridevikoushik31/openstack,noironetworks/nova,eonpatapon/nova,gspilio/nova,yrobla/nova,maoy/zknova,zaina/nova,dims/nova,maoy/zknova,luogangyi/bcec-nova,affo/nova,Stavitsky/nova,isyippee/nova,JianyuWang/nova,OpenAcademy-OpenStack/nova-scheduler,klmitch/nova,klmitch/nova,zzicewind/nova,akash1808/nova,ted-gould/nova,mgagne/nova,dstroppa/openstack-smartos-nova-grizzly,CEG-FYP-OpenStack/scheduler,cyx1231st/nova,badock/nova,plumgrid/plumgrid-nova,maheshp/novatest,joker946/nova,cloudbase/nova,saleemjaveds/https-github.com-openstack-nova,leilihh/nova,ewindisch/nova,mandeepdhami/nova,maoy/zknova,BeyondTheClouds/nova,hanlind/nova,devendermishrajio/nova_test_latest,thomasem/nova,JioCloud/nova_test_latest,rahulunair/nova,CCI-MOC/nova,shootstar/novatest,zhimin711/nova,Triv90/Nova,sacharya/nova,apporc/nova,gspilio/nova,tanglei528/nova,tudorvio/nova,rickerc/nova_audit,NeCTAR-RC/nova,cernops/nova,sebrandon1/nova,fnordahl/nova,leilihh/novaha,petrutlucian94/nova,Yuriy-Leonov/nova,devendermishrajio/nova_test_latest,akash1808/nova_test_latest,alexandrucoman/vbox-nova-driver,aristanetworks/arista-ovs-nova,Brocade-OpenSource/OpenStack-DNRM-Nova,kimjaejoong/nova,sacharya/nova,openstack/nova,fajoy/nova,blueboxgroup/nova,vmturbo/nova,mikalstill/nova,cloudbase/nova,cloudbase/nova