Reset constraints - forget the previously set constraints

I found this useful while working through a tutorial on "intermediate" auto layout techniques. Basically I want to forget / reset all of the previously set constraints and then apply new styles with a new set. Normally in iOS you would simply clear the UIView's constraints collection, but I realized that teacup keeps its own cache of previously set constraints.

For ease of use (!), I also clear the teacup constraints recursively to allow the user to decide where in the tree they (i.e. I) want to reset.

I don't know if this goes against the intent of this great library (as I am new to teacup), so please feel free to suggest any better alternative behavior.