Have monit match pppd proc by regex, not PID file
Have monit match pppd proc by regex, not PID file

The PID file is not written, either because pppd is mis-configured
or because it is not written until the connection is up.  This causes
monit to continually restart pppd.

Fixes https://github.com/IthacaThings/ttn-multitech-cm/issues/88

IthacaThings/ttn-multitech-cm,IthacaThings/ttn-multitech-cm