[evlatests] level settings

[Walter Brisken]

I've injected more and updated level t304 attenuator settings into evlaparm 
database.  The values used can be found in

/home/parallax/evla/levels/levelparms

As for antenna 14 I plotted the sync detector voltage vs. sampler RMS in order 
to determine the output voltage range to aim for.  For antenna 16 the sampler 
RMS range corresponding to peak sync detector voltage was between about 9 and 
18. Given good weather during yesterdays tests pointing up we'll assume that 
Tsys was more or less minimal then.  If any significant changes are made to the 
receivers or data path between the receivers and samplers then these values 
should be updated.

All IFs/Bands for 14 and all IFs/Bands except for L and Q on antenna 16 are up 
to date.

-W