[evlatests] More interesting results from Modcomp-Free data

[Rick Perley]

    1) The raw data filled through AIPS shows normal amplitudes -- 
roughly in tens of Janskys, as always. 

    2) The amplitude drops noted previously are not accompanied by Tsys 
changes. 

    3) All Tsys values look entirely normal, with the expected values, 
and reflecting the known (showery, thunderstormy) weather. 

    4) The EVLA antennas, statistically speaking, are no different than 
VLA antennas.