fixed old imports in docs

[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
• [ ] I've updated the versions based on Semantic Versioning
  • [ ] setup.py
  • [ ] talos/__init__.py
  • [ ] docs/index.html
  • [ ] docs/_coverpage.md

Docs

• [x] Docs are updated

Tests

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

---