[feat] adding linting

[gardlt]

• added flake8
• corrected linting issues

[mark-burnett]

@gardlt Thanks for this, I will take a look later today.

[alanmeadows]

These look like sane changes.

One item I would add to the sort of "basic building blocks we have everywhere" is that I like the approach deckhand is taking toward using oslo config to actually generate its config file. It creates an opportunity for us to apply our same openstack-helm configuration management techniques to our undercloud applications:

https://github.com/att-comdev/deckhand/tree/master/etc/deckhand

[/cc @fmontei]