Replace start.sh with supervisord

[micolous]

Supervisord is a Python daemon which is designed to run other (primarily Python-based) programs and keep them running in UNIX-like environments.

start.sh could be replaced with a supervisor configuration file (/etc/supervisord/doorlock.conf) like this:

[program:doorlock]
command=/usr/local/bin/doorlock.py
autostart=true
autorestart=true

This would enable the process to be controlled easily with the supervisorctl command:

# supervisorctl stop doorlock
# supervisorctl start doorlock
# supervisorctl restart doorlock