More simplifications, preparing to make LeoLog and LeoBody classes independent of the HighLevelInterface class.  All tests pass.
Added WrapperAPI class.  The body of each method is, in effect, a declaration of the return type of the method.
Added much better explanation from today's post of wrappers and widgets.
Removed unused getFocus method from wrappers.  Note: the setFocus method is used, and is required!

Leo build: 20140903095621