- various attempts at a better way to handle boolean/csg operations:
 * attempting to keep the "geometry" within a mesh to always be the same instance , even
after a csg operation : unconclusive so far
 * issue due to how the THREE.js webgl renderer handles object initialization : ie
currently it is not possible to swap out dynamically the "geometry" in a mesh
 * minor tweaks here and there
- LOTS of experimentation on the visual editor:
 * implemented a hack/workaround for linkedCloning + csg operations:
  * uses a new "Part" class , which wraps the actualy geometry/mesh within itself..
  * and an event based approach : whenever the "original" gets updated, an event is
dispatched to all linked copies, and they update their geometry instances
  * implementation is awfully hack and convulted, only configured for cubes, but it works!
  * added lots of notes regarding this, and the various other possible issue I found

 * added experimental "mirroring" (x axis) support : not good at all , see the notes

 * added a Subtraction  "command/ (history item)" :
  * undo redo is clunky behind the scenes but works for the subtract csg operation

 * added visual helper to show the "original <-> linkedClone" relationships
  * also added a real time update "hack" for this (so whenever an object is moved,
the helper gets refreshed)
  * added small visual effect that makes the right hand operands of "subtract" become
translucent temporarly after an operation

 * lots of minor tweaks, adjustements etc etc
- continued fleshing out the list of commands in the shape-creator
(perhaps I should rename this one):
  * added clone, linkedCLone & mirrorX