tools: adding gluster logs

Gluster logs support added to hypervisors, collects gluster logs
only if gluster is enabled in respective cluster.

Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=856127

Change-Id: I756aea7457c2cd7c9c7b0b842149110f5f392abb
Signed-off-by: Aravinda VK <avishwan@redhat.com>