apychal 1.9.6

Async version of pychal (drop-in replacement to pychallonge)

This is the async version of pychal.

Please note that it :

• Only supports Python 3.6+ (modern asyncio, removed legacy code).
• Replaces requests with aiohttp (which makes this module asynchronous).

That's it for the main differences, otherwise it should be the same to use as the original.

Why don't you submit this as a PR? I don't trust my tech skills to be honest, what I did here was very simple. However it breaks compatibility with older versions of Python, which can be an issue. If you're going to use an async version of pychal, I think you're already aware of the reason why.