Some important changes for cone structure

1. Previously, we mis-used the SS log data as linear data for absorbance
2. Change peak efficiency from .3 to 0.67. Peak efficiency should take
PODs into account and the total peak efficiency is around .3
3. Implement coneGet(cone, ‘energy fundamentals’ routine
4. Add some comments to explain why our computation is different from
PTB (Fundamentals refer to different things)
5. Accomplish validation script between iset cones and ptb