Add tag for deco dives

Fixes #85

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Add translations for 'deco' tag

These were done by me through the advanced linguistic process known as
"pattern matching". I doubt that this is right in all the languages...

For some reason two new Swiss-German translations snuck in as well.

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