This drops support for the pre-challenge-response authentication scheme
(i.e. the scheme in use before Zarel/Pokemon-Showdown@7dbd8cfec5 on
February 8, 2013), and, by doing so, simplifies quite a bit of the
authentication code.
In particular, it is no longer necessary to make any database queries in
index.php, which reduces our database use significantly and also moves us
closer to the goal of the index page being static HTML.
This commit allows the new psim.us domain to use the cookies and
`localStorage` of play.pokemonshowdown.com. Teams and prefs are
initially loaded from the play.pokemonshowdown.com `localStorage` and
changes to teams and prefs are written back to the
play.pokemonshowdown.com `localStorage`.
This commit also implements a few other things for the new psim.us
domain (implemented by Zarel):
- URIs of the form serverid.psim.us load the server `serverid`
- the naked domain now loads the lobby
