Distance Transforms

[pattonw]

Is your feature request related to a problem? Please describe.
We want fast distance transforms calculated on arrays with multiple labels. This is non trivial, and very slow if not done well. We have some custom code that does significantly better than most naive solutions, but I think it could be done better.

Describe the solution you'd like
The Seung lab apparently has a very nicely packaged solution for just this problem, I think we should use their code (https://github.com/seung-lab/euclidean-distance-transform-3d)

Describe alternatives you've considered
I have searched around a decent amount and I am unaware of any other packages that do what we need.