gluster: Fix output format compatibility of removeBrickStatus

Rebalance status and Remove brick status have common output structure,
engine uses common code to parse the vdsm output of both verbs.

This patch fixes the incompatibility in remove brick status output.
(As this verb is not consumed by engine/RHS-C yet, its OK to differ
in compatibility now)

Output:
    {'summary': {
        'filesScanned': INT,
        'filesMoved': INT,
        'filesFailed': INT,
        'filesSkipped': INT,
        'totalSizeMoved': INT,
        'status': STRING
    },
    'hosts': [{
        'name': STRING,
        'filesScanned': INT,
        'filesMoved': INT,
        'filesFailed': INT,
        'filesSkipped': INT,
        'totalSizeMoved': INT,
        'status': STRING
    }..]}

Change-Id: Id7996af2a779119a6f703f309ad377c8a425b1c5
Signed-off-by: Aravinda VK <avishwan@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/20108
Reviewed-by: Bala.FA <barumuga@redhat.com>
Reviewed-by: Dan Kenigsberg <danken@redhat.com>