Set cover level using emulated_hue

[ptc]

Description:

implemented support to set cover level using emulated_hue.
Added missing tests for cover in emulated_hue component.

Checklist:

• The code change is tested and works locally.
• Local tests pass with tox. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated in home-assistant.io

If the code communicates with devices, web services, or third-party tools:

• New dependencies have been added to the REQUIREMENTS variable (example).
• New dependencies are only imported inside functions that use them (example).
• New or updated dependencies have been added to requirements_all.txt by running script/gen_requirements_all.py.
• New files were added to .coveragerc.

If the code does not interact with devices:

• Tests have been added to verify that the new code works.

[dgomes]

Looks good,

just wondering how this works from a user point of view. What command should you give Alexa (eg) ?

[ptc]

It behaves like a lamp:
Alexa turn off front window (to close)
Alexa turn on front window (to open)
Alexa set front window to 50 percent
Alexa set front window to 20% (only 20% light aka 80% closed)

[andre-richter]

Thanks for working on this! 👍

[ptc]

@dgomes anything else to fix in your opinion?