#55 Custom content on About page

[Eugene Kalinin]

There should be some place where we could put
information intended for our users, like descriptions for
various field values (what do we mean by severity 1 bug
here, when is the next release for project xxx scheduled
and so on - local policy stuff), tips (like bugid#xxx in
comments), links to external sites, announcements etc.
A good place for this is the About page - there's plenty
of free space on it.
This content should be just any HTML.