skyring: Filter clusters list based on status
skyring: Filter clusters list based on status

Modified the clusters list api as below
  - GET /api/<ver>/clusters?status=<ok/warning/error>

Change-Id: I75752e5deb78317cf94143f6cdf2217b3a87817a
Signed-off-by: Shubhendu <abf833e62503b33bb0dfae62bb381d87d91f8de1@redhat.com>

skyrings/skyring,skyrings/skyring,skyrings/skyring,skyrings/skyring