Tweaked Dirichlet distribution + new tests
fix methods for chi distribution
Merge pull request #101 from simonbyrne/chi

fix methods for chi distribution
Merge pull request #100 from simonbyrne/master

fix noncentral distributions
tweak Dirichlet MLE
Refactored Dirichlet MLE -- allow also allows input either a matrix of samples or pre-computed E[log p].
add constants.jl
add twoπ to constants
relax the requirement of Dirichlet MLE
Improved Dirichlet sampling + revised var/cov functions for Dirichlet
various tweaks, rand for noncentral