Add Counter to Helpers

[danimart1991]

Proposed change

Add Counter to Helpers UI.

Type of change

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

Example configuration

counter:

Additional information

• This PR fixes or closes issue: fixes Add counter to the helper UI #4998
• This PR is related to issue:
• Link to documentation pull request:

Checklist

• The code change is tested and works locally.
• There is no commented out code in this PR.
• 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

[danimart1991]

I'm currently working on this. A few questions:

• I have problems saving the value of the restore bool value while using a Switch. Maybe I forgot something or I'm using the wrong component?
• Actually default_config component doesn't include Counter so I think is necessary an extra step to include it.

[bramkragten]

Yes, counter should be added to default_config in the core repo.