complete user auth

[vlahm]

needs password reset and possibly email verification.

we'll need to send emails in both cases. we could configure our existing mail forward server at mail.macrosheds.org as an SMTP server. or we could use something like mailgun or sendgrid. the latter definitely has a free tier that will work for us.

[vlahm]

This guide will help. If it's totally incompatible with the way auth is currently set up, looks like we could rebuild things in accordance with its preceding article.