Inserts blanks into likelihood list at the appropriate locations if the negative binomial fails to converge to a solution, or the negative bionomial or Poisson lognormal return -inf.  The second case should no longer be occurring, due to an earlier fix, but the work around is still there.
Merge remote-tracking branch 'upstream/master'
Tweaks discussion point about multiple explanations for a single model.
Merge pull request #35 from embaldridge/master

Fixes output mistake, more writing.