Add service to group switches

[MrEbbinghaus]

This PR adds device_info for the switches, creating a service that groups those switches, improving organization.

I imagine that in the future, we could add the configuration variables as entities too and add them to the service. This way they could be used by automations.

To-do:

• [x] Add the "main" switch to the service

Some screenshots:

[basnijholt]

@all-contributors please add @MrEbbinghaus for code

[allcontributors[bot]]

@basnijholt

I've put up a pull request to add @MrEbbinghaus! :tada:

[basnijholt]

Thanks a lot for this contribution @MrEbbinghaus!

[MrEbbinghaus]

Thanks a lot for this contribution @MrEbbinghaus!

You're welcome. Thanks for the great integration.