Support optional hvac_mode parameter in set_temperature on climate

[Akeboshiwind]

Fixes #47

[jeatheak]

Hey Thank you for your commit/PR 😃 Look ok for me, I will try to test it as soon as possible.

Did you mean the parameters in this Doc? https://www.home-assistant.io/integrations/climate/#service-climateset_temperature

[Akeboshiwind]

Yes, exactly 👍