Implement cycle select on election pages

[noahmanger]

Changing the cycle should load the election for the selected cycle.

[noahmanger]

@jmcarp what are your thoughts on this? I know that we're doing cycles different for election pages than others. I actually could see replacing the cycle select with buttons / links that take you to the different years (though that list will get long). There's some sense to that. Each election is a kind of a unique thing, unlike candidates or committees that stay consistent over time. At the same time, I see the case for treating them the same.