Python 3.7 features, states 3.6 requirement

[se7enmilgram]

I was being lazy and built python 3.6 on a Pi Zero W (no mean feat) in order to get the updated version of the project, only to get the following message:

AttributeError: module 'asyncio' has no attribute 'get_running_loop'

A little google searching and it seems as though this is a 3.7+ feature. Probably just need to spec 3.7+ as the requirement.

Otherwise, very cool project!

[flyte]

Ah, I think this get_running_loop reference may be from within the asyncio-mqtt client library. I happen to be a contributor on that library too, so I'll see if it's possible to fix 3.6 compatibility on there. Thanks for the report!