Variety of improvements and additions:

 * Much improved list screen for elections.
 * Initial voter-based interface based around tokens.
 * New uniq_token regenerating library.

Left things a little bit unstable including:

 * uniq_token should be refactored to provide only a class method.
 * voter list review page is unwritten
 * rankings are committed to the database but some sort somewhere seems
   to be botching things.