Added Priority to all of the boolean directives documentation

[mark0978]

None of the boolean directives have their priority listed in the docs. In addition, required and open appear to be missing documentation altogether. I didn't fix the latter problem since I'm not sure what either of them actually do.

[mary-poppins]

Thanks for the PR!

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If you need to make changes to your pull request, you can update the commit with git commit --amend.
Then, update the pull request with git push -f.

Thanks again for your help!

[mary-poppins]

Thanks for the PR!

• Contributor signed CLA now or in the past
  • If you just signed, leave a comment here with your real name
• PR's commit messages follow the commit message format

If you need to make changes to your pull request, you can update the commit with git commit --amend.
Then, update the pull request with git push -f.

Thanks again for your help!

[IgorMinar]

CLA signature verified! Thank you!

Someone from the team will now triage your PR and it will be processed based on the determined priority (doc updates and fixes with tests are prioritized over other changes).