gluster: During import check host existence by UUID

Modified to check the existence of hosts in the cluster by UUID, while
impporting the hosts into console which got added from CLI.
This makes sure no self entries get listed because of virbr0 bridge and
also resolves the hanging issue while importing the hosts added from
CLI.

Also added logic to discard a host ifrom the list if there is no fingerprint
available for the same.

Change-Id: I60f5fdf16c6b2cf717a041b34f9e62e0ac6b78f3
Bug-Url: https://bugzilla.redhat.com/1021773
Signed-off-by: Shubhendu Tripathi <shtripat@redhat.com>