Compute trolands from retinal irradiance in watts/um2-wlinterval. The answer is
returned in trolands/wlinterval and can be summed to get trolands.
See Wyszecki and Stiles, 1982, p. 103 for the conversions.
Input variables: irradianceWatts - retinal irradiance in watts/um2-wlinterval.
irradianceS - the wavelength sampling information for the relativeSpectrum.
photopic - what kind of trolands: ‘Photopic’ (Default), ‘JuddVos’, ‘Scotopic’.
species, source - passed directly to EyeLength to determine length of eye in mm.
These values inherit the default behaviors of EyeLength.
07/18/03 dhb Wrote it.
04/09/12 dhb Debug. This was apparently never quite finished.