Feature request:- convolution Wasserstein distances

[kowshikthopalli]

Hi, I wish to request to add the code from the paper- http://people.csail.mit.edu/jsolomon/assets/convolutional_w2.compressed.pdf
Their matlab code is here https://github.com/gpeyre/2015-SIGGRAPH-convolutional-ot.git

Thanks
Kowshik

[rflamary]

added the feature in PR #64