Make the new "Unverified Email" behavior more clear to other users

Summary:
Ref T12268. Ref T12157. When you mention or interact with a user who is unlikely to be able to respond (for example, because their account is disabled), we try to show a colored dot to provide a hint about this.

Recently, we no longer send any normal mail to unverified addresses. However, the rules for showing a dot haven't been updated yet, so they only care about this if auth.require-verification is set. This can be misleading, because if you say Hey @alice, what do you think about this? and she hasn't verified her email, you may not get a response.

Update the rule so users with unverified email addresses get a grey dot in all cases. The hint is basically "you shouldn't expect a response from this user".

Make the meaning of this hint more clear on the hovercard and profile.

Also:

• Allow the non-ajax version of the hovercard page (which is basically only useful for testing hovercards) accept ?names=... so you can just plug usernames, hashtags, etc., in there.
• Fix a bug where the user's join date was based on their profile creation date instead of account creation date on the hovercard. Users may not have a profile creation date (if they never changed any account details), and it may be different from their account creation date.

Test Plan: {F2998517}

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T12268, T12157

Differential Revision: https://secure.phabricator.com/D17374