xenapi - use management network to reach OS VM

Devstack used the HOST_IP_IFACE to reach the OpenStack VM through ssh.
This patch changes this behavior, so that the IP address of the
interface connected to the management network will be used.

Related to blueprint xenapi-devstack-cleanup

Change-Id: I7f34d973870792d60a33ea512901d9b0d422150b
Move hypervisor-specific code into a case statement

Change-Id: Id799506f180ac81d493f49de140cc079338430aa
use SERVICE_HOST intead of HOST_IP for quantum services

The other services, like nova, glance and cinder, use SERVICE_HOST
instead of HOST_IP to configure their server listening addresses.
This is more friendly to multi-node quantum deployment.

Change-Id: Ibee22ef59d532e8f7004d8e4582015d303d15404
Remove temporary logic for Quantum auth_token transition

When Quantum auth_token configuration were moved to quantum.conf,
the temporary logic to disable auth_token in api-paste.ini was added
to avoid gating test failures of patches based on the version with
api-paste.ini auth_token configurations.
This temporary logic is no longer needed.

Change-Id: I539301a338d5ada01c83af5e9cf203849a67c6c1
On unstack : clean up network namespaces created by quantum

Also removes OVS ports

Fix Bug #1156837

Change-Id: Id4178c0a12a3ada76403a57a736a9c7a908d6a4a
Merge "use SERVICE_HOST intead of HOST_IP for quantum services"
Merge "On unstack : clean up network namespaces created by quantum"
Merge "Remove temporary logic for Quantum auth_token transition"
Merge "xenapi - use management network to reach OS VM"
Merge "Move hypervisor-specific code into a case statement"
Merge branch 'master' of github.com:openstack-dev/devstack