Merge pull request #5 from adamilardi/master

Fixed some bugs?
Adding alternative dirichlet calc from multinomial data
Added Chinese restaurant process sampling
http://en.wikipedia.org/wiki/Chinese_restaurant_process`
 fix assert
Merge pull request #6 from adamilardi/master

Add docs, iteration param and bug fix
Merge pull request #7 from adamilardi/crp

Chinese restaurant process sampling