Fix missing translations for webservice responses

The webservice backend sends responses in English. Let's do a better job
presenting those in the users preferred language.

Fixes #714

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Fix planner gas consumption

We need to start out with valid SAC rates in the diveplan.

Thanks to Gaetan for finding this and suggesting a different fix - this
seems cleaner to me.

Reported-by: Gaetan Bisson <bisson@archlinux.org>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>