Add instructions to GPS map window title

This is not what I really wanted (which was the ability to add text to the
map itself), but it should be at least somewhat better than what we have
today (which is a complete lack of instructions).

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

This should re-enable to text for "Gas Used" and introduces the new text
for the map window title from commit 21401578c620 ("Add instructions to
GPS map window title").

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