Fixed major bug in acceptance/rejection for steps.

* The acceptance/rejection criteria for the affine-invariance
  MCMC is not the same as MH.  I was using the MH criteria.
Avoid generating random number if prob of acceptance >= 1.
Merge branch 'base'

Conflicts:
	include/global_settings.h
Adjust affine messages down to avoid overlap with pofd_messages in main branch
Merge branch 'base'

Conflicts:
	include/global_settings.h