Created a discovery handler using asyncio

[rokam]

I did create a MideaDiscovery class that handles discovery with some async events. With this, we'll be able to automatically support discovery inside homeassistant.

I wasn't able to test it with v1 and v3 devices, I'm glad if someone test it for me.

[seppe912]

got error Error : (<class 'TypeError'>, TypeError('support_testv3() takes 3 positional arguments but 4 were given'), <traceback object at 0x75eefb48>)

need to remove self on scanner.py line 39: _device = await self.support_testv3(account, password) then OK with my V3

[rokam]

got error Error : (<class 'TypeError'>, TypeError('support_testv3() takes 3 positional arguments but 4 were given'), <traceback object at 0x75eefb48>)

need to remove self on scanner.py line 39: _device = await self.support_testv3(account, password) then OK with my V3

Thanks. Fixed

[rokam]

@seppe912 I did some changes, can you please test it again with v3 devices?

[mac-zhou]

@rokam Sorry, please reopen a PR. 😄

[rokam]

Ok