This commit alters views for the following models to use the markdown cache if
present:
* AbuseReport
* Appearance
* ApplicationSetting
* BroadcastMessage
* Group
* Issue
* Label
* MergeRequest
* Milestone
* Project
At the same time, calls to `escape_once` have been moved into the `single_line`
Banzai pipeline, so they can't be missed out by accident and the work is done
at save, rather than render, time.
Add a new application setting, after_sign_up_text. This is text to be
rendered as Markdown and shown on the 'almost there' page after a user
signs up, but before they've confirmed their account.
Tweak the styles for that page so that centered lists look reasonable.
