Add Hidden Markov Model Matcher

[nreinicke]

This is a larger scope issue that will likely need to be split into smaller sub issues

Add a new Hidden Markov Model matcher class that implements the algorithm originally described in this paper.

Some other resources:

• https://github.com/valhalla/valhalla/blob/master/docs/meili/algorithms.md

[bernardotepedino]

Hi. Was this implemented? Is there any documentation to use mappymatch with HMM?

[nreinicke]

Unfortunately this hasn't yet been implemented but we welcome any contributions!