New layout for topiclist lists

New layout for .topiclist lists
Also replaces topiclist list with table for UCP notification settings

Adjustments for .html files include:
- Wrapping content of <dt> in <div class="list-inner">
- Adding extra tab for content of .list-inner
- Adding class name to <ul class="topiclist"> to indicate how many columns are there

RFC: http://area51.phpbb.com/phpBB/viewtopic.php?f=108&t=44139
Ticket: http://tracker.phpbb.com/browse/PHPBB3-11489