fixed create subnet for Quantum
Merge remote-tracking branch 'upstream/develop' into develop
future proof additions and compute fixes

getNetworkURL method added
do not return from Cinder.removeVolume until removal completes
fixed createPort endpoint
assign provider subnet id to vms where applicable
allow cloud error message to bubble up to console
bugzid: 3380 determine openstack provider in consistent way
bugzid 3395: change authentication context to region_account caching level
Merge pull request #33 from daniellemayne/develop

Develop - caching fixes, remove volume and create subnet fixes, allow cloud errors to bubble up