Add support for DS2760 1-Wire TypeK Thermocouple

[droberg]

Breaking change

Proposed change

Add support for DS2760 1-Wire TypeK Thermocouple

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)
• 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: Add onewire ds2760 information home-assistant.io#20986

The DS2760 Li+ Battery Monitor [1] can easily be used as a thermocouple
converter because it has both temperature and voltage reading.
The use is supported through OWFS [2]. Unfortunately the original
app note from Maxim is no longer available online.

[1] https://pdfserv.maximintegrated.com/en/ds/DS2760.pdf
[2] https://owfs.org/uploads/ds2760.html

Checklist

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

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

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