Added Normal known precision, Poisson distributions + alternate hazard function

[kmsravindra]

For someone whoever is interested, I have added Normal known precision, poisson distributions in my fork below. Also tried adding another type of hazard function which is normally distributed over time. Usage of the same is updated in Example code as well. Find my fork here - https://github.com/kmsravindra/bayesian_changepoint_detection

[hildensia]

Hi Ravindra,

would you consider to send a pull request? I'm happy to merge into master!

Thanks for the additional features.

Johannes

[kmsravindra]

@hildensia , Sure, will do. Please give me some time.