Unet artifact

Right now we have an artifact that comes out from our unet (you can see it in either the raw featurization of the unet or in the segmentation artifact) - for example see below:
<img width="1200" alt="Screen Shot 2019-10-03 at 2 26 40 PM" src="https://user-images.githubusercontent.com/6531703/66165779-602a3e80-e5ea-11e9-8a02-e1878fb78231.png">
