Add YUI library for drag and drop

Added the modules recommended by this demo:
    http://yuilibrary.com/yui/docs/dd/list-drag.html

Created a min file by using the YUI configurator:
    http://yuilibrary.com/yui/configurator/
Home: Add rudimentary drag-and-drop sorting

Use the YUI demo in our situation to rearrange
DOM elements in a story list. Does not save the
new order of elements or anything like that,
just moves things around.