Add force_config_drive to openstack::all

Currently the openstack::all class doesn't expose a parameter for the
force_config_drive option in nova.conf.  The underlying ::nova::compute
class does have such a parameter.  This commit exposes
force_config_drive as a parameter to the openstack::all class and passes
it down to the ::nova::compute class appropriately.  By default it is
set to false to preserve backward compatibility.

Change-Id: Iab0f0b1f358e22bfe2e79cf9c9adbd83f77eef7a
Implements: blueprint force-config-drive-for-all-class
Added parameter for memcached_servers

Nova module allows for an array of memcached servers
to be passed to it. This change presents a parameter
in openstack::controller to pass it to openstack::nova::controller

Change-Id: I3a5636ac93076da7fc5c664b9054a2d7d6f84183
Merge "Add force_config_drive to openstack::all"
Merge "Added parameter for memcached_servers"