Attempt to create a sensible pyspark structure boilerplate. Heavily work in progress so it's constantly breaking

Bazel, was the chosen one even after agonizing pains of researching and prototyping alternatives (Buck, Pants). It still have its quirks, but insert Thanos memes

"You could not live with your own failure." "Where did that bring you? Back to me."

• chain_transforms: compose multiple transforms on a DataFrame

• df.transforms API is added to follow the Scala API

• Bazel 2.0.0
• Grit & Patience (trust me, you need it. I do :C)