added a callback for monitoring power draw on GPU

[mikkokotila]

You want to make a PR to Talos

Thanks so much :) First, please take a moment to carefully check through the below items:

Sanity

• [x] I'm aware of the implications of the proposed changes
• [x] Code is PEP8
• [x] I'm making the PR to master

Docs

• [x] Docs are updated
• [x] Docs version is correct (index.html and _coverpage.md)

Tests

• [x] Changes have gone through actual use testing
• [x] All local tests have passed (run ./test.sh in /talos)
• [ ] Tests have been updated to reflect the changes

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[pep8speaks]

Hello @mikkokotila! Thanks for opening this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file talos/utils/power_draw_callback.py:

Line 27:80: E501 line too long (95 > 79 characters)