rework code into the widget object, and add start, stop, and rotate callbacks as modeled on the jquery-ui resizeable code.
add start, rotate, stop callbacks to demo and documentation.
Added "angle" option

It wasn't possible to specify the starting angle of a rotatable
so I've added an angle option. I also discovered a bug with the
custom handle code which I fixed at the same time. Finally, I
added some extra demos.
Added custom handle

Think I managed to miss actually committing the changes last time around.
This is what you get for coding on the bus! Committed now.
fix bad reference to performRotation method.
Merge branch 'master' of https://github.com/thehunmonkgroup/jquery-ui-rotatable into thehunmonkgroup-master

Conflicts:
	README.md
	demo.html
	jquery.ui.rotatable.js
	jquery.ui.rotatable.min.js
Merge branch 'thehunmonkgroup-master'