R1:a65e3812cbde

Move slowvote loading logic into Query class

Summary: Mostly straightforward. Also fixed a couple of error/darkconsole things.

Test Plan:
- Created poll;
- viewed poll;
- voted in poll;
- used `V6` and `{V6}` markup styles in poll.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Differential Revision: https://secure.phabricator.com/D6458