add yule simon cdf

[lingium]

Description

This issue is a feature proposal.

As a continuation of https://github.com/stan-dev/math/issues/3219, we will add cdf for yule simon distribution.

Expected Output

real yule_simon_cdf(ints n, reals alpha)

Checklist

This will require a yule_simon_cdf with analytical derivatives.

• [ ] cdf
• [ ] test of cdf

Current Version:

v5.1.0