* Signup: if entering an existing email, don't admit that the email
exists. Instead, send a specialized email to its address.
* Search: no longer search for users by email address.
* Login: always hash the incoming password on user not found, to take
constant time compared to when the user did exist.
* Fix a pagination bug when a private (shy account) views a non-friend's
photo gallery.
* Users who set their Profile Picture to "friends only" or "private" can have
their avatar be private all over the website to users who are not their
friends or not granted access.
* Users who are not your friends see a yellow placeholder avatar, and users
not granted access to a private Profile Pic sees a purple avatar.
* Admin users see these same placeholder avatars most places too (on search,
forums, comments, etc.) if the user did not friend or grant the admin. But
admins ALWAYS see it on their Profile Page directly, for ability to moderate.
* Fix marking Notifications as read: clicking the link in an unread notification
now will wait on the ajax request to finish before allowing the redirect.
* Update the FAQ
Implement block lists. They work like friend lists but are unidirectional,
but take effect in both directions (blocker and blockee can not see one
another on the site -- except admin users can always see all users).
* Profile page says 404
* User gallery says 404
* User search page filters out blocked users
* Compose endpoint blocks sending messages to blocked users (except admin)
* Site Gallery filters photos by blocked (and uncertified) users
* Inbox page hides chat list for blocked users (can still read the chat
history if you have a link to the old thread)
* Add "forgot password" workflow.
* Add ability to change user email address (confirmation link sent)
* Add ability to change user's password.
* Add rate limiter to deter brute force login attempts.
* Add user deep delete functionality (delete account).
* Ping user LastLoginAt every 8 hours for long-lived session cookies.
* Add age filters to user search page.
* Add sort options to user search (last login, created, username/name)
