hokusai setup/run to balk if executed in a non-git directory.

[artsyjian]

It seems hokusai setup can be run in any directory.

A first-time Hokusai user is likely to run setup in home directory. I demonstrate:

artsy:~ jxu$ hokusai setup
Created project repo 585031190124.dkr.ecr.us-east-1.amazonaws.com/jxu

And, unknowingly creates a Docker repository named after the home dir (as well as dropping Hokusai ymls into the dir). Over time, a lot of these empty Docker repos are created.

hokusai staging/production run... can also be executed in any directory and if done it spawns a Kubernetes pod that attempts to pull Docker image from a repository named after that directory, and crash loops.

I would like Hokusai to be more strict about the directory where these commands can be run, probably allow them only in Git local repos.