Fix typo

Signed-off-by: Miika Turkia <miika.turkia@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Print numerical value of mean depth

This will print the numerical value of mean depth to the profile graph.

Fixes #405

Signed-off-by: Miika Turkia <miika.turkia@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Use helper function to display mean depth with correct unit

In commit 528d0ea0e7bd ("Print numerical value of mean depth") Miika once
again forgot the three non-metric countries on this planet... :-)

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