support for multiple clusters in dashboard

This is to allow the users to select the cluster
which the data needs to be displayed.

dashboard/osd-viz/graph pages will be refreshed
according to the selection of the cluster.

Signed-off-by: Kanagaraj M <kmayilsa@redhat.com>
Merge pull request #58 from kmkanagaraj/multi-cluster-support

support for multiple clusters in dashboard
support for multiple clusters in manage

This is to allow the users to select the cluster
which the configuration needs to be displayed.

pages will be refreshed automatically
according to the selection of the cluster.

Signed-off-by: Kanagaraj M <kmayilsa@redhat.com>