[DEV-2153] Add leaderboard.
[DEV-2153] Move leaderboard template to skins. Change template name in view.
[DEV-2153] Update view to support hideous Askbot pagination.
[DEV-2153] Update template to fix "Nothing found."
[DEV-2153] Fix base url to carry a query string.
[DEV-2153] Replace user_card macro with customized contents.
[DEV-2153] Re-class new user card & add styles to override.css.
[DEV-2153] Tweaks to leaderboard template.
[DEV-2153] Tweak styles.
[DEV-2153] Add position div to leaderboard.
[DEV-2153] Style leaderboard position element.
[DEV-2153] Add ordering by last_seen.
[DEV-2153] Remove unused template pieces.
[DEV-2153] Change page title of leaderboard.
[DEV-2153] Add position to leaderboard for logged-in user.
[DEV-2153] Add padding to leaderboard list element.
[DEV-2153] Change header link to people to leaderboard. Capitalize keywords in header.
[DEV-2153] Remove unused imports.
[DEV-2153] Correct query in Leaderboard view.
[DEV-2153] Rework user get_leaderboard_position method.