save datatable state across page refreshes

Change-Id: I41a3ba292626fd8ceeeffb8ed643afc3f7bb8813
Reviewed-on: http://review.couchbase.org/24904
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Ronnie Sun <ronnie@couchbase.com>
Tested-by: Ronnie Sun <ronnie@couchbase.com>