GitLab

Should be added back by next release

So that it doesn't have a whole bunch of tabs in funny places

Also update the title and add a breadcrumb title. Credits can do because
the page was rewritten a couple of days ago from scratch and is not
copyrightable anyway.

Stub pages which are not in the Makefile

Reflow and make other minor changes at the same time

And fix up other minor stylistic issues