Add option to automatically handle token

[gredin]

I'm using your work in my home project (controlling beer fermentation temperature). So, first: thanks!

I think clients of this library don't need to know the token acquisiton details.
This PR intends to hide these implementation details.

P.S. Also, getDeviceStatus method as a bonus.

[codetheweb]

Thank you for your contributions!

I think we should keep the token methods public, as some applications may want to get/refresh the token according to their own logic - otherwise, this could be considered a breaking change.

[gredin]

I understand the breaking change issue.
What do you think about keeping the methods public, but adding an optional arg automaticToken* (default: false) in the constructor that would enable the automatic acquisition/refresh behaviour?

(*The naming needs improvement, but you get the idea.)

[codetheweb]

I think that's a good idea, then we can check that property in the token methods and throw an error if it's true and the consumer is trying to call it anyways.

Maybe handleToken?

[gredin]

I'm back. What do you think about the changes?

Also, I fixed the choice of the sign method according to Tuya documentation:

TuyaCloud provide two sign algorithm based on different scenario：

- token related interface（v1.0/token&v1.0/token/{refresh_token}）：sign = HMAC-SHA256(client_id + t, secret).toUpperCase()

- business interface(except token interfaces)：sign = HMAC-SHA256(client_id + access_token + t, secret).toUpperCase()```

[codetheweb]

👌
Thanks for the contributions!

[codetheweb]

Published in v1.1.0.