Add more comments to eval_acor
Rearrange functions to match order of unit tests
Comment cabs2
Add unit test for eval_acor
Fix improper summing of Gauss-Legendre points

By mistake, I had basically implemented:

    y += w[N] (f[N] + w[N-1] (f[N-1] + ... + w[1] f[1]))

instead of:

    y = w[1] f[1] + w[2] f[2] + ... + w[N] f[N]
Shorten some long lines
Fine-tune time of arrival prior
Make module init function Python 3 compatible
Drop bayestar_sky_map_toa_snr
Move unit tests to main source file
Add --f-low option to bayestar_realize_coincs
Wrap long lines
Oops, wrong weights
Fix segfault due to missing argument
Tune thinning and number of samples per bin
Add option to postprocess MCMC samples with KDE
Match polarization sign in signal_amplitude_model & realize_coincs

I have checked that this is the sign convention that is used by
gstlal_inspiral.

This patch also adds a unit test for signal_amplitude_model.
Factor out awkward type punning
Conjugate nominal SNR to match convention in paper

Likelihood should depend on zhat * conj(z)
Match littlehope default SNR threshold to realize_coincs