Ticket/Issue, What does this resolve?

Resolves #123

Open Questions:

• Who should be able to see this directory? I feel like Private users shouldn't be able too, but if a user's profile is public they're able to show it anyone regardless if they're a registered public/private user or not.

Description

This PR

• Creates a user directory that is only accessible to registered users who have set their profiles to public.
• Does not allow private Users to view the directory through a callback :no_creeps . Still allows them to view User show pages, not sure if that should change
• Adds a button for the User directory to nav

QA Notes and Testing

Working on it

Screenshot/Video

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