major unbound docs improvements

[seniorm0ment]

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• [ x ] I have made only one major change in my proposed changes.
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What does this PR aim to accomplish?: Added more detail to unbound docs, and make it easier to obtain a more secure, better performing setup

How does this PR accomplish the above?: See commits

What documentation changes (if any) are needed to support this PR?: None to my knowledge

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[github-actions[bot]]

This pull request has conflicts, please resolve those before we can evaluate the pull request.

[github-actions[bot]]

Existing merge conflicts have not been addressed. This PR is considered abandoned.