Yelp Changes

[Don Scorgie <Don Scorgie org>]

(All in one, to save annoying everyone with multiple emails)

Yelp has been branched for 2.20.  We're a little late in this.

We have also just merged a monster rework branch into trunk, which
introduces a lot of new / changed strings (sorry!).

The UI for displaying docbook help has changed slightly (the menu is now
down the right), and we now depend on Rarian instead of scrollkeeper.
This shouldn't pose too much of a problem since rarian replaced
scrollkeeper in jhbuild yesterday.

I've tried to update the POTFILES.in file and think I've got it all, but
would love someone to check over the changes.

Note to translators: Rarian doesn't have any translatable strings, so no
new strings have been introduced by the change to Rarian.

Thanks
Don