Branch/drawing rect

@eric79 @youngca 
The text, image, and sprite drawing objects all now have a border.

Also, fixed the dragging of icons so that the dragging is relative to the last move.
Is `this.nodePoint` intended to be different on every client?  That makes me nervous since it means that each user's model won't actually be identical since it violates the [Pitfall](https://virtual.wf/documentation.html#pitfalls) that says, "Do not reference *this.moniker* in the model".  Can you think of any other way that we could do this that wouldn't risk breaking the model?