Emit Unregistered Mark Warning in Command Line Usage

[mberkowitz03]

<!-

• Allow maintainers to push and squash when merging my commits. Please uncheck this if you prefer to squash the commits yourself.

Closes #10514
Emit a warning when -m is used with unregistered marks

• Create a new changelog file in the changelog folder, with a name like <ISSUE NUMBER>.<TYPE>.rst. See changelog/README.rst for details.
• Add yourself to AUTHORS in alphabetical order.
  -->

[mberkowitz03]

Sorry - some of the commits are from work on another issue that I accidentally had migrated to this branch. I'd like this PR squashed, anyway.

[mberkowitz03]

I don't love adding arguments to the expression compiler, but I couldn't find a more appropriate way to do it, because of the way command line arguments are parsed. Open to suggestions!

[Zac-HD]

Thanks Max! This looks pretty good to me; we'll just need some tests to make sure we'll notice if a future PR would break it 🙂