* add verified column to users table
* add database functions to check if verified, or to verify
* getting there
* verification check
* use base64 urlsafe no pad
* add verification client
* clippy
* correct docs
* fix integration tests
If XDG_RUNTIME_DIR is set, put the socket file there.
If not, default to storing it in our data dir. We cannot default to a
path such as /run/user/$UID/ because it does not exist on all systems.
Any system running systemd will set this var by default, and ensure that
the directory it points to is correctly setup.
