Figure out how to use Fil with Metaflow

[itamarst]

@conda decorator might be good starting point?

[itamarst]

Probably going to focus initial efforts on Fil's commercial, production-grade counterpart (https://pythonspeed.com/products/fil4prod/) since that is specifically designed to be always on, so makes more sense as starting point for production framework integration.

Might apply what I learned there here.