Implement location look up tool

[jenniferthibault]

Most recent mockups here, and discussion in #313 :

[jmcarp]

@jenniferthibault @noahmanger do we want an option to select an election cycle here, or is the idea to restrict to upcoming elections?

[noahmanger]

Good question. I think it's ok to leave it off. Because the results are actually Districts, I think it makes sense to not have the option. You can view past cycles by going to an election page and changing the cycle there.

I also like the simplicity of having this just be a 1 or 2 question tool. We may learn that people want a cycle select, but I think it's ok to not have it for now.

[jmcarp]

This exists.