Filter candidate lists by race

[lottspot]

The current frontend provides two different candidate list pages-- one for each race. We need to add the appropriate filtering to each page so only candidates running for the requested office are displayed.

Alternatively, we can do away with distinguishing the candidate lists by race and display everything on one page.

[lottspot]

Personally, I'm highly partial to the latter solution. I think it opens up the ability to provide searching and filtering of the entire list, so the user can reduce the list according to her own parameters, rather than having to use whatever arbitrary division we provide her