handle all output from pfilamps pi

The pfilamps system occasionally blurts out a diagnostic when the calling program is not expecting one. In this case a lamp was measured as a bit faint during the pre-firing test, and spit out argon lamp is faint or off: val,thresh=0.6392,0.7 when the caller was querying for the lamps to warm up.

Deal with it. Maybe route some of the warnings to log file only.