Version bump (2.0.5 -> 2.1a)
Fix image preview making window show scrollbars
Change PluginManager for better support

- Add some simple error handling (logging to console)
- Add onEnable and onDisable events for the plugin to do things at
  start and end
- Add access to simple per-plugin "global" values that are defined in
  the plugin
Change Image Preview plugin to use new PluginManager features
Fix some bugs with clickable player names

- Change the CSS to make them glow when hoevered over instead of being
  underlined
- Fix the RegExp to find all usernames at the beginning of a normal
  chat line (including whispers)
Add link to new server-provided chat.css styling
Fix whisper RegExp

This change also modifies the receive hook to supply the message
wrapped in a jQuery object.
Make the username highlighter work again
Add ability to hide online player list
Add a timeout value to AJAX calls
Some general code cleanup

- Move the smiley image around a bit in CSS
- Fix some small code formatting problems
- Remove the unused selectElement() function
Add some (very) simple error logging for the chat loader
Add tab-completion for names with non-name characters in front
Make dialog's close button use same as tabs
Remove duplicate GET from message sending
Only allow one tab per whisper target
Fix invasion messages to comply with server
Change the way channels are stored again

This new system relies on a semi-unique tagging system to treat each
channel's metadata as part of an object. It necessitates the changing
of a large portion of code just to recreate the old functionality. The
change should leave everything as it was before with two exceptions:
* Tabs that have been closed will retain their history (and can be
  reopened)
* The <hr> used to show old chat history now show on all channels
  (including whisper channels) when joining
Small cleanup related to previous commit

- Remove some now unused variables
- Fix some things using those variables
- Fix a RegExp bug in the script tag detection
Swtich some parts to be more consistent with styles