- more work done on undo/redo system for three-editor:
 * various UI additions : clicking on "U"/"R" (stand ins for icons) does the undo redo operations as well
 * clicking on an item in the history undoes it (not finished)
 * small cleanup in the undo/redo code
 * added operation index
- further enhancements to undo/redo and operation history navigation:
 * now users can click on an item in history to go back to that point (undos or redos)
 * changed the way the redo stack is handled : uses shift/unshift instead of push/pop, to handle
the "reversed" order compared to undo stack in a more comprehensive fashion
 * some (failed) experiments with polymer templating tricks
- modified three-stats to initialize on ready callback instead of 'created'