Updating executables in linux bin directory.

Updating linux bin with statically-linked executables compiled on a
Rocks cluster (kwyjibo).
Updating executables in mac bin directory.

Updating mac bin with statically-linked (well, at least GSL is
statically linked) binaries built under Darwin 10.8 on a Mac running OsX
10.6.8 (jasper).
Merge branch 'master' of phylo.bio.ku.edu:PyMsBayes

Merging updated linux and mac executables.
Updating `NumberOfDivergencesSummary` class.

Updating incorrect references to `npairs` to `self.config.npairs` in the
`_simulate_psi_prior_probs` method.