Hide comments

Added module that allows you to hide/minimize a thread from the top level comment for easier navigation through the comments.  It's a hack cause as you know, HN is all tables with barely any classes, but it works! Please excuse my code.  I also included jQuery to help me traverse through the DOM.  Also I barely added styling to the toggleThread span, just wanted to get it functioning. Please feel free to make it look nicer.

The only indicator that a reply is top level is that there's a div inside that handles indentation by adding width.  Top level comments have a 0px width.