Remove reference frequency option from BAYESTAR

The reference frequency shift is no longer necessary because MBTA is now
shifting triggers to common mass parameters. For pipelines that report
triggers from identical templates in all detectors, the reference
frequency shift only serves to introduce a bias into the geocentered
arrival time.
First attempt at MCMC implementation of toa_phoa_snr
Try toa_phoa_snr likelihood with completed square trick
No need to set GSL error handler here

These functions do not raise GSL errors.
Unified MCMC interface
Use Barankin bound for TOA weight
Match likelihood for MCMC to inner loop
Rescale distance in log likelihood, like in main loop
I am an idiot: cos(i) can be negative.
Shrink limits of integration over arrival time

Not because I think it is correct or well-justified, but because this is
the value that I used originally.
Use normal distribution cross term

This now departs again from the original inner loop.