Implement noise correlations.

[eacharles]

I haven't turned on the noise correlations, as implemented by the Noise class in the noise.py.

I think that most of the code is there, I just need to check it and test it against OG BoloCalc.

[eacharles]

I've added the correlations, but I did so rather blindly, just taking values from a pickle file to compute the correlations based on wavenumber. Keeping this open until we validate this.