distribution.js: implementing mean, variance and sample methods for poisson
distribution.js: implementing mean, variance and sample methods for poisson

ggonzale/jstat,akrawitz/jstat,JeebsM/jstat,jstat/jstat,NorthDecoder/jstat,jamescgibson/jstat,jstat/jstat,cmpolis/jstat,JeebsM/jstat,smarden1/jstat,NorthDecoder/jstat,smarden1/jstat,akrawitz/jstat,ggonzale/jstat