Web: Added basic rank management.
Moved useful web-related functions to a separate file.
Rewritten the Permissions page to use cRankManager.
Rewritten the Players webadmin tab.

Players are displayed per world, with their rank, and they can be kicked, PMed or edited simply from the list. The player details show their position and allow changing their rank.
Fixed PM edit box too large.
Implemented in-game /rank and /listranks commands.
Web Players: update the player's rank in-game.
Fixed offline UUIDs in rank command.
Fixed web player details when player disconnects.
Updated the rank-based console commands for cRankManager API.
Alpha-sorted the console command handlers.
Implemented the unrank console command.
Merge branch 'master' into Ranks
Unified the code style and usage texts for console commands.
Merge pull request #83 from mc-server/Ranks

Rewriting permission system to use UUIDs and Ranks