[LinuxPPS] nmea/atom configuration

[gnu not unix]

Hi everyone--

I had had just the nmea/linuxpps configured with GPS (and a couple
of LAN hosts) and was seeing +/-20 microseconds of flap. 

Then, I just added the atom driver to the same /proc/pps/sources
(so that both atom and nmea use the same device and edge) and
it has smoothed out the plot by a factor of 10 (+/-2 microseconds).
There are still a few 10's of microseconds spikes which might be
the heating turning on and off, though.

Very interesting plot:

http://www.wraith.sf.ca.us/ntp/oddplot/index.html

Latest updated plot:

http://www.wraith.sf.ca.us/ntp/rrd/index.html

../Steven