Add ability to have a party title and description

[mpherman]

The party title could prepend or replace "Holy Grail Leaders" on the leaderboard data table.
A party description could then be put in smaller font underneath to give some context to who runs the party and who should be a member, etc.

Will need to modify:
-party database model
-party leaderboard page
-party manage page
-api methods for updating these