Implement profile pages

[davidsandoz]

We can see information about some people on some pages, but the information shown depends on the context of the page. The idea would then be to have a page for each user which give all the public information about them (current and previous positions in the federation, games they refereed, games they played, ...) The private information could also be shown, but of course not publicly, only if a use has the rights to see the information.

The profile pages could be accessible through the path /people/:username