SGP/EBBR/E35 - SHF #4 incorrect at times

Soil Heat Flow 4 was incorrect at times, sometimes resulting in incorrect sensible and 
latent heat fluxes.

• Surface soil heat flux, average of fluxes 1-5(surface_soil_heat_flux_avg)
• Surface soil heat flux 4(surface_soil_heat_flux_4)
• Soil heat flow 4, corrected for soil moisture(corr_soil_heat_flow_4)
• Soil heat flow 4(soil_heat_flow_4)
• Surface latent heat flux(latent_heat_flux)
• Surface sensible heat flux(sensible_heat_flux)