Usage:

Check out the code, then open up canvas_test.html
in your browser.

Input an equation, and mess around. We'd love feedback,
so leave us some comments over on the blog at 
http://rcos-touch-of-math.blogspot.com/

You can move terms and operators across an equals sign.
Also, to use the merge without touch, enter the indices
of the two terms. For example:
	1+2+3 = a
To merge 1+2+3, enter 0 and 4, and click to see it happen.
On a touch screen, just move your two blocks closer
together.