UI polish

inspired by http://drupaltest.campfirenow.com/, i request the following:

- increase the width and height of the chat message input box. ideally, this box grows to fill the available space.
- i don't know how they do this, but they don't have a scrolling textbox inside the page. their chat scrollbar *is* the page scrollbar. this may not be possible in drupal without theme help, but maybe some clever person knows.
- i like their table layout which clearly separates username column from chat text. note that format_name() already truncates long names so we don't have to worry about that ... use light grey table borders for each cell.