Add a Tunnel end-point variable for Neutron configuration

The HOST_IP address is being used as IP address
for end-point tunnel configruation. A new variable is
needed to specify a different IP address for the tunnel
end-point that Neutron will use

Change-Id: Ic7fb4853df167e78bf882af6a712b903db754dc2
Closes-bug: #1340433
add python-mock to testonly package list

Python-mock is needed by most of OpenStack for testability. Add
this is a testonly package. This should fix current issues with
functional tests in OpenStack that use devstack, but not tox to
run their tests.

Closes-Bug: #1341507

Change-Id: I26cbe42ace75554bae993a6d849c3b4ac649c78e
Support multiple Cinder backend types

This is the first step in supporting multiple Cinder backend types at
once.  It initially converts the existing hard-coded multi-lvm support
to a new cinder_backends driver form.  Eventually the cinder_plugins
will be converted to this form so they can be enabled more than just
one at a time using CINDER_ENABLED_BACKENDS.

The default configuration should be identical to the previous defaults,
including for both True and False values of CINDER_MULTI_LVM_BACKEND.

The existing cinder_plugins are expected to be removed when this is
complete. They should continue to work until they have been converted.

Add wait for c-api to ensure it is started before continuing.

Change-Id: I93b8ef32832269d730c76a6dc24ddb4f20c6d9df
Merge "Add a Tunnel end-point variable for Neutron configuration"
Merge "Support multiple Cinder backend types"