Implement new transition kernel for bounded domains
Add joint pdf docs for invlogitgaussian
Add docs for invlogitgaussianvectorrv
Add docs for InvLogitVectorRealizer
Add docs for the new TK
Fix up gpmsa example
Fix some bugs in the invlogit distribution

1. Deal with the pdf at the boundary better
2. Fix a bug where the wrong transform was being taken for left-open domains
Update regression tests with new reference solns

We need to do this because the transition kernal as changed for DRAM and so
different samples are drawn.
Update ignores.  It's bad these keep piling up