delete 'tempSpectralData' records outside irradiance thresholds
fixed query bug in fn 'GetDaySpectralData', if not using references
clearer threshold deletion diagnostics
steps towards custom functions in NDVI calculations
additional fields in 'tmpSpectalData' table, for processing
start on formula translations
new fn 'creatAndAssignDBFn', to use arbitrary irradiance formulas in queries
tester fn for 'creatAndAssignDBFn'
simplified 'createAndAssignDBFn' to 'assignDBFn'
testing 'assignDBFn' when there is only one parameter
adapt code to used scidb.assignDBFn for irradiance formulas
test, fill in 'tmpSpectralData' field by update using DB fn
fill in other 'tmpSpectralData' fields by Update using DB fns
added tests for IR and VIS db fns, and moved to validation section
updated NDVI in 'tmpSpectralData' table
calculate NDVI in 'tmpSpectralData' when useRef = 0