and add a simple unit test function.

Now takes an optional shader

reorganise the CIE-1931 and CIE-1964 tables.

a wavelength to saturated xyY function based on the standard observer
data.

white value in case we want to convert XYZ to L*a*b* with something
else than D65.

add XYZ to xyY conversion (which gives us a pretty accurate xy graph of
the sRGB gamut), and normalise XYZ using a D65 white point.

function for CIE L*a*b* values.

files on some Unix systems.

subtelties to avoid polluting Doxygen.

when a stream is not found in the vertex declaration at bind time.