Add support to fully_kiosk for hybrid local push/pull switches using MQTT

[mheath]

Breaking change

Proposed change

This is the first step in a larger goal of adding a motion binary sensor to to the Fully Kiosk integration. This commit provides support for using MQTT to update the screen and screen saver switches immediately (when MQTT is enabled in HA and in FKB) instead of waiting to poll the kiosk. Also, there are other entities that could have local push support using MQTT. I will submit PRs for that once this PR is accepted.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue:
• Link to documentation pull request:

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
• I have followed the development checklist
• The code has been formatted using Black (black --fast homeassistant tests)
• Tests have been added to verify that the new code works.

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

• Documentation added/updated for www.home-assistant.io

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• The manifest file has all fields filled out correctly.
  Updated and included derived files by running: python3 -m script.hassfest.
• New or updated dependencies have been added to requirements_all.txt.
  Updated by running python3 -m script.gen_requirements_all.
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To help with the load of incoming pull requests:

• I have reviewed two other open pull requests in this repository.

[home-assistant]

Hey there @cgarwood, mind taking a look at this pull request as it has been labeled with an integration (fully_kiosk) you are listed as a code owner for? Thanks!

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[cgarwood]

Looks OK to me, but might be good for someone more familiar with MQTT to take a quick look.

[mheath]

Is there anything I can do to get this in someone's queue to get a second review?

[home-assistant]

Please take a look at the requested changes, and use the Ready for review button when you are done, thanks 👍

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[mheath]

@emontnemery I finally got around to finishing the change you requested. Could you please take another look and let me know if there's anything that needs to be fixed for this to get merged?

[mheath]

@emontnemery Could you take another look at this PR?

[emontnemery]

LGTM, thanks @mheath 👍

[MartinHjelmare]

Please move all the MQTT data and topic parsing to the 3rd party library. The library can accept callbacks for MQTT subscribe and publish that Home Assistant can provide and then the library can handle the logic and parsing as needed.