contributing reinforced learning modules

[yawetse]

hi @targos

I have to modules I'd like to contribute ML.UpperConfidenceBound and ML.ThompsonSampling, I'd love to add them to ML if you think it's helpful to have a Reinforced Learning Section.

Check out : https://github.com/repetere/modelscript/blob/master/src/ReinforcedLearning.js, I also have full test coverage for them and tried to conform to the naming conventions of ml.js because I'm a huge fan of what you guys have built!