Add tooltip that tells user how to edit dive information

This adds the tooltip just to the Dive Notes page of the notebook area -
that's where people are tempted to try to do "edit in-place" which we
currently don't support.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Place Info and Stats page at the top of notebook page

This seems to look better than the previous "centered" setup when
switching between notebook pages.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>