MB-12222: display "what's this" tooltips on mouse hover
MB-12222: display "what's this" tooltips on mouse hover

This implementation differs from current UI.
I think it's much better show up tooltip on hover rather than on click.

Change-Id: Id5b1cadbf2f8912d43c783592f1333bcbd0d3d8b
Reviewed-on: http://review.couchbase.org/56743
Reviewed-by: Dave Finlay <7b10a9ed9f70e64c30b07607a671ae61c33f14c8@couchbase.com>
Tested-by: Dave Finlay <7b10a9ed9f70e64c30b07607a671ae61c33f14c8@couchbase.com>

membase/ns_server,ceejatec/ns_server,ceejatec/ns_server,membase/ns_server,ceejatec/ns_server,ceejatec/ns_server,ceejatec/ns_server,membase/ns_server,membase/ns_server,membase/ns_server,membase/ns_server,ceejatec/ns_server