Fix signing_dir option for auth_token middleware.
Fix signing_dir option for auth_token middleware.

The keystone auth_token middleware expects an option named
'signing_dir'.  The sample api-paste.ini file for nova defined
'signing_dirname' instead.

Fix bug 1073858.

Change-Id: Ie9a3df73a8d9d52b48d6e0bcce0aae762af929a9

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