New integration - CometMonitor (#5466)
This PR introduces a new monitoring option - `CometMonitor` which comes
up as an official integration with
[CometML](https://www.comet.com/site/).
The new monitor is covered with unit tests.
Notes:
* We've updated `docs/code-docs/source/monitor.rst` but it doesn't look
used anymore
* We've updated the "Monitoring Module" section name in `config-json.md`
to be generic so the next integration won't require updating it.
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Co-authored-by: Boris Feld <lothiraldan@gmail.com>
Co-authored-by: Logan Adams <114770087+loadams@users.noreply.github.com>
