Remember cluster selection across reloads

Whenever the user selects a cluster, id of the cluster
will be stored in the browser's localstorage. So when
the user reloads the page or move from dashboard to manage app,
last selected cluster will be fetched from localstorage
and the page will be rendered accordingly.

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