Implement simulators leaderboard
A bit of error handling.
Merge branch 'SimulatorsLeaderboard2' of git://github.com/dpen2000/codecombat into dpen2000-SimulatorsLeaderboard2
A few fixes and cleanup for #831.
Merge branch 'master' of https://github.com/codecombat/codecombat
Fixed footer background color on LevelView.
Fixed #310 by tweaking the styling to emphasize stroke over fill.
Merge branch 'master' into production