Summary:
See PHI1027. Currently, the "Welcome" mail always tells users to set a password. This definitely isn't helpful if an install doesn't have password auth enabled.
We can't necessarily guess what they're supposed to do, so just give them generic instructions ("set up your account"). Upcoming changes will give administrators more control over the mail content.
Test Plan: Sent both versions of the mail, used `bin/mail show-outbound` to inspect them for correctness.
Reviewers: amckinley
Reviewed By: amckinley
Differential Revision: https://secure.phabricator.com/D19990
7f950f520b