This change modifies our connection plugins to allow us to use nspawn
type containers. The change will pull in the container_type variable and
set the padding for commands accordingly.
While the module has been setup to default to LXC which ensures we've no
conflicts with existing deployments, the container_check function has been
set to ignore "nspawn" type containers until we have a suitable/reliable
method to connect to them without envoking ssh.
Change-Id: I8877c244af6458ca9840ea0519ab457a726feefd
Signed-off-by: Kevin Carter <kevin.carter@rackspace.com>