Neutron: Remove get_namespace from API extensions
Neutron: Remove get_namespace from API extensions

Based on the conversation on the ML.

http://lists.openstack.org/pipermail/openstack-dev/2015-June/066219.html

Change-Id: I95a0aba75d10d15a94b0eeaed80a8f7a22b85625

redhat-cip/tempest,JioCloud/tempest,masayukig/tempest,nunogt/tempest,manasi24/tempest,yamt/tempest,manasi24/jiocloud-tempest-qatempest,yamt/tempest,varunarya10/tempest,sebrandon1/tempest,roopali8/tempest,akash1808/tempest,neerja28/Tempest,rakeshmi/tempest,nunogt/tempest,afaheem88/tempest,flyingfish007/tempest,dkalashnik/tempest,NexusIS/tempest,dkalashnik/tempest,bigswitch/tempest,flyingfish007/tempest,izadorozhna/tempest,vedujoshi/tempest,neerja28/Tempest,Juniper/tempest,hayderimran7/tempest,openstack/tempest,jaspreetw/tempest,sebrandon1/tempest,Juraci/tempest,xbezdick/tempest,Juniper/tempest,cisco-openstack/tempest,tonyli71/tempest,NexusIS/tempest,tudorvio/tempest,tonyli71/tempest,LIS/lis-tempest,izadorozhna/tempest,openstack/tempest,tudorvio/tempest,pandeyop/tempest,pczerkas/tempest,pandeyop/tempest,hayderimran7/tempest,Tesora/tesora-tempest,LIS/lis-tempest,vedujoshi/tempest,manasi24/tempest,jaspreetw/tempest,afaheem88/tempest,cisco-openstack/tempest,varunarya10/tempest,JioCloud/tempest,roopali8/tempest,alinbalutoiu/tempest,bigswitch/tempest,Tesora/tesora-tempest,zsoltdudas/lis-tempest,pczerkas/tempest,redhat-cip/tempest,Juraci/tempest,zsoltdudas/lis-tempest,xbezdick/tempest,masayukig/tempest,rakeshmi/tempest,manasi24/jiocloud-tempest-qatempest,alinbalutoiu/tempest,akash1808/tempest