Move gluster/{cli,exception,hostname,__init__}.py to vdsm rpm

This move is being done so that vdsm code using gluster cli
doesn't have the need to depend on vdsm-gluster rpm

Change-Id: I079facc5d4fc7c3bfd8460731e6708fce242164e
Signed-off-by: Deepak C Shetty <deepakcs@linux.vnet.ibm.com>
Reviewed-on: http://gerrit.ovirt.org/8033
Reviewed-by: ShaoHe Feng <shaohef@linux.vnet.ibm.com>
Reviewed-by: Dan Kenigsberg <danken@redhat.com>