"bsrn" platform at SGP data problem

As reported in ARM Technical Report ARM-TR-002, the 'bsrn' data at the SGP CF
was not in agreement with the co-located SIRS E13 and C1 data. Subsequent
discussion led to the conclusion that ther was a voltage problem with the
'bsrn' data logger. In development and testing of the Diffuse Correction and
Best Estimate Flux VAPs, it has been shown that all 'bsrn' data, all
instruments, suffered this data logger problem. The result is noisy and
slightly offset values, seemingly at random throughout the period from October
1998 through the end of the 'bsrn' data stream and it's replacement by the BRS
system. All this data needs to be colored 'questionable', and all data users
need to be informed that either the SIRS E13 or SIRS C1 data should be used
instead.

Color "bsrn" data as "questionable", and inform users that the co-located
SIRSS E13 and/or SIRS C1 data should be used instead.

• Calculated Downwelling Longwave Hemispheric Irradiance, Ventilated Pyrgeometer
  from 20s data(calculated_down_long_hemisp)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer, Minima(down_long_hemisp_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyrgeometer, Standard
  Deviation(down_short_hemisp_std)
• Ventilated Pyrgeometer Dome Temperature(dome_temperature)
• Downwelling shortwave hemispheric irradiance, pyranometer, maxima(down_short_hemisp_max)
• Detector flux (Down-welling pyrgeometer thermopile voltage * PIR-DIR calib-coef)
  Calculated value from 20s data(detector_flux)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyrgeometer, Full
  corrected (Mean absolute deviation)(dsdh_full_corrected)
• Shortwave direct normal irradiance, pyrheliometer, minima(short_direct_normal_min)
• Downwelling Shortwave Hemispheric Irradiance, Pyranometer, Minima(down_short_hemisp_min)
• Case temperature(case_temperature)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Pyrgeometer, Minima(down_short_diffuse_hemisp_min)
• Shortwave direct normal irradiance, pyrheliometer(short_direct_normal)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyrgeometer, Dutton
  corrected(dsdh_dutton_corrected)
• Effective temperature(effective_temperature)
• Downwelling longwave hemispheric irradiance, pyrgeometer(down_long_hemisp)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Pyranometer, Standard
  Deviation(down_short_diffuse_hemisp_std)
• Downwelling shortwave diffuse hemispheric irradiance, pyranometer, maxima(down_short_diffuse_hemisp_max)
• Downwelling Longwave Hemispheric Irradiance, Ventilated Pyrgeometer, Standard
  Deviation(down_long_hemisp_std)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer, Maxima(down_long_hemisp_max)

• Average pyrgeometer thermopile voltage(psig)
• Average pyrgeometer dome thermistor resistance(ptdome)
• Average reference voltage(vref)
• Standard deviation for pyrgeometer dome thermistor resistance(stdome)
• Average battery voltage(vbat)
• Standard deviation for reference(svref)
• Standard deviation for shaded pyranometer(spsp1)
• Standard deviation for unshaded pyranometer(spsp2)
• Standard deviation for pyrgeometer thermopile(ssig)
• Direct-beam normal solar irradiance(nip)
• Average shaded pyranometer voltage(psp1)
• Average unshaded pyranometer voltage(psp2)
• Standard deviation for pyrheliometer(snip)
• Standard deviation for pyrgeometer case thermistor resistance(stcase)
• Average pyrgeometer case thermistor resistance(ptcase)

• (Raw data stream - documentation not supported)

• Average unshaded pyranometer voltage(psp2)
• Average shaded pyranometer voltage(psp1)
• Direct-beam normal solar irradiance(nip)
• Average pyrgeometer thermopile voltage(psig)