Increase the spectral range for major chromophores

[janakarana]

Is your feature request related to a problem? Please describe.
The VTS spectral panel uses the mua data specified in "Spectra.txt" and "SpectralDictionary.xml" for spectral panel calculations. Current spectral ranges for H2O, HbO2, Hb, Fat and Melanin are limited to 400-1000nm, 250-1000nm, 250-1000nm, 600-1000nm and 600-1000nm respectively.

Describe the solution you'd like
This issue is added to extend the spectral range for H2O, HbO2, Hb, Fat and Melanin.

Describe alternatives you've considered
None

Additional context
I have updated "Spectra.txt" and "SpectralDictionary.xml" from following references. This information can be used to update https://github.com/VirtualPhotonics/Vts.Gui.Wpf/wiki/Spectral-Panel

Hb and HbO2:
250 nm -1000 nm: https://omlc.org/spectra/hemoglobin/summary.html
1001 nm - 1600 nm: Nachabe et. al, Biomedical Optics Express 2(3) (2011)

H2O:
250 nm – 715nm: https://omlc.org/spectra/water/data/segelstein81.txt
716 nm – 1600 nm: https://omlc.org/spectra/water/data/kou93b.txt

Fat:
429 nm – 1049 nm: https://omlc.org/spectra/fat/fat.txt (Van Veen 2004)
1050 nm – 1600 nm: Nachabe et. al, Journal of Biomedical Optics 15(3) (2010)

Melanin:
250 nm - 1600 nm: https://omlc.org/spectra/melanin/mua.html Jacques McAuliffe plot data

Updated Spectra.txt and SpectralDictionary.txt files are here.
Spectra.txt
SpectralDictionary.txt