Improved sqrt layout in some browsers (take 2)

I tested this change on Firefox (27), IE (8 & 10), and Chrome (37) on Windows and Chrome (39), Firefox (30), and Safari (7) on Mac OS X 10.9.4.

Firefox and IE rendering changed looked good before the change and surprisingly didn't change with this change.

Chrome (Mac & Windows) and Firefox (Mac) both improved substantially at large (> 20px) font sizes.  Safari's rendering improved a little bit.

It doesn't solve all rendering issues with ```\sqrt```, but it's a step in the right direction.