Utility for change the password of dovecot intallations.
It basically do following:
/usr/bin/doveadm auth test user@domain old_pass && \
/usr/local/bin/htpasswd -sb /VMAIL/AUTH/domain user new_pass
It uses doveadm auth, instead of htpasswd -v because on some dovecot installations, there are password schemas that are not recognized by htpasswd.
Because of security, everything is hardcoded. You need to change it to match your configuration.