Synchronize with upstream Tock to remove 04-rtt.patch

Add Github workflows

- python code formatting is tested with yapf
- cron workflow to run cargo audit
- Don't run on latest

This avoids running workflows when it's not needed

These should do the checks for us.
Not an expert though so it may need a bit of tweaking before they do
what we want them to do.

Configure pylint for Google's Python style.

Adding pylint configuration, VSCode configuration to lint on save and
make the deploy.py script compliant.

Fix errors in deploy script.

Document troubleshooting on OS X

Better handling of OpenSSL generated keys.