Add Queens support

Parametrize keystone endpoints for opencontrail. Now all values for
opencontrail identity are hardcoded for port 35357. This commit give
user option to overide these values in cluster level. For example
OpenStack Queens realease use only port 5000.

Change vnc_api_lib.ini file to be able to create resources in
opencontrail with both identity versions v2 and v3.

Related to: PROD-20297

Change-Id: I19e395c3e88e43e3968f28f660a02300dbf0b17e
8 files changed