Second cran submission.
thames_mixtures() added which computes an estimate
for the reciprocal marginal likelihood
overlapgraph() added which computes the overlap
graph and criterion of overlap (co)
compute_nobile_identity() added which estimates the
log marginal likelihood
alltopsorts_recursion() added which computes all
topological orderings
This is a resubmission. In this version I have:
removed the command par() in all files, vignettes and demos,
added 3 optional parameters to thames_mixtures.