Upgrade to aiocoap 0.4b3

[balloob]

This upgrades pytradfri to use aiocoap 0.4b3 and migrates credential management to the new approach.

I don't have a Tradfri gateway here so I only got as far as that aiocoap was able to find the credentials. Was not able to verify.

Fixes #185

Can be tested using:

python3 examples/example_async.py <IP> -K <KEY ON BOTTOM OF GATEWAY>

This is a breaking change. Async API Factory now needs to be set using await APIFActory.init(…)

[balloob]

The other flake8 errors will be squashed once we migrate this repo to black once this is merged.

[ludeeus]

Both initial and secondary (without key) seems to work as expected 👍 with my limited test (connect)

container# python examples/example_async.py 192.168.2.100 -K XXXXXXXXXXXXX
[]
No lights found!
[<65542 - TRADFRI blind (FYRTUR block-out roller blind)>]
Waiting for observation to end (2 mins)
Try altering any light in the app, and watch the events!

container# python examples/example_async.py 192.168.2.100
[]
No lights found!
[<65542 - TRADFRI blind (FYRTUR block-out roller blind)>]
Waiting for observation to end (2 mins)
Try altering any light in the app, and watch the events!

I don't actually have something paired to it for further testing (the blinds are elsewhere now)

[houndci-bot]

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