Gluster to handle ENOSPC (Error 28) correctly

A gluster volume could yield an ENOSPC condition seeing
that a volume is full.  This needed to handled correctly.
Added error handling.

BUG: 985253

https://bugzilla.redhat.com/show_bug.cgi?id=985253

Change-Id: I85472c0a81a354a2796327fead606da3a938d4bf
Signed-off-by: Chetan Risbud <crisbud@redhat.com>
Reviewed-on: http://review.gluster.org/5362
Reviewed-by: Peter Portante <pportant@redhat.com>
Reviewed-by: Luis Pabon <lpabon@redhat.com>
Tested-by: Luis Pabon <lpabon@redhat.com>