Add Poisson Distribution

[jacobseiler]

Great tool!

I went to the website to try and use it to explore a Poisson Distribution and noticed it was missing! This is a function in Scipy so was wondering if it could be added?

[rdzudzar]

Thank you!

The v1.0 of the app contains only continuous distributions, a work is in progress to include other types of distributions - and the discrete ones are on the top of my list, which is where the Posisson distribution will be included.