Implement storage of alliance selection pickings

Alliance selection pickings are stored via a JSON
property in the Event model. It supports both picks
and declines, but there is no datafeed to populate
declines yet.

Picks are sourced from a Google Docs spreadsheet
maintained by CD members (<http://www.chiefdelphi.com/forums/showpost.php?p=1351639&postcount=14>).

On the frontend, only the eliminations bracket is
updated to use the proper order of teams, in the
future it could be exposed in other views.

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I wasn't really sure how to add it to cron_main.py, since that seemed to require some other stuff. Do I just write a cron_controller thing? How often should something like this run?

The CSV parser also needs a little more work to make it more robust, right now it'll spit back bad data if the spreadsheet isn't fully filled out.