Theme reviews: create dashboard and allow point accrual (bug 903598)

Let's get theme reviewers caught up on the features app and add-on reviewers enjoy!

1) Dashboard

Theme reviewers should have a dashboard at https://marketplace.firefox.com/reviewers/themes, modeled after what app reviewers have at https://marketplace.firefox.com/reviewers. Instead of an Update Reviews column, we should show Flagged Reviews

2) Point accrual

Theme reviewers should earn points for the reviews they perform, and be included on the leaderboards (both https://marketplace.firefox.com/reviewers/leaderboard/ and in the snapshot above the review queues).

+5 for each review, whether it's new, flagged, or a re-review.

Exclude admins from accumulating points.

# Screenshots

![screen shot 2013-08-19 at 1 28 07 pm](https://f.cloud.github.com/assets/674727/989055/0f76cfa4-090e-11e3-9e24-cc09bb43979d.png)
![screen shot 2013-08-19 at 1 28 31 pm](https://f.cloud.github.com/assets/674727/989057/106d6814-090e-11e3-96c0-a2be9b22d5cd.png)