Allows users to update email addresses, passwords, usernames, and avatars through /user.
Removes traces of autoincrement attempts.
Fixes some error displays throughout the app.
Fixes erroneous swig template for displaying the avatar on the /user page.
Fixes label "for" attributes on /user page.
Adds client-side confirmation to changing email addresses and passwords in /user.
Makes /user page send an ajax request to update values.