[jsxilinx]: Minor cleanup
[jsxilinx]: Cleanup. Mostly-generic widgets are now within a 'widgets.js' script
[jsxilinx]: Further cleanup. Most mats and objs are now created fully from World.js
[js]: WorldLoader now supports an OnLoad callback, implemented using JQuery's Deferreds
[jsxilinx]: Every object and material is now created through the WorldLoader system