Administration page

[eseverson]

Add an administration tab allowing the admin to:

• Start/stop the contest at will
  • Set start and stop times to automatically open the contest
    *Manage multiple contests:
    • Have one contest for practice then another for the actual competition and easily switch the active contest
    • Have the ability to have multiple contests running at the same time, allowing there to be multiple categories of users, each part of a different contest, or even have users be part of multiple groups so that they are able to submit problems to more than one competition at a time
  • Various other settings for the behavior of the server/contest