Add sorting options to leaderboard

[yoshivb]

It would be nice if you could sort the leaderboard by wealth, items and rank.
Username is not needed but I also don't think it would be bad to have it.

I think you should be able to both sort ascending as well as descending.

Obviously sorting by wealth and rank would result in the same thing at this moment, but I think it would be nice to future proof it incase the rank logic changes to no longer be entirely based on wealth alone.