Revamp the structure of contests and its children

* Switch back to nested resources/routes. I believe fiollowing the conventions will keep me out of
  trouble so I'll stick to nested resources/routes for that reason

* EAK expects you to nest code like you nest your routes in the router. So ContestsIndexRoute should
  be in routes/contests/index and the corresponding template should be in templates/contests/index.
  Also, /contests/:id uses ContestsContestRoute, ContestsContestController and contests/contest
  template. Nesting the files makes this a little less verbose