advance width support including:

* exposure to CPS
* ability to update using CPS
* updated CPS value respected during export to UFO

advance height is also added.
I have no idea how that got to be there. fixed, just ran test.sh. Though it seems that travis ci has had the build pass, which is much more concerning. Unless JS does something funny when you close a scope inside the declaration of a variable instead of closing the block scope at that point.