Slots

- Re-factored code and docs to make online trials the default usage.
- Fixed instantiation of n arms for online trials.

- Changed docstring style to Numpy format
- jcbozonier added the Bayesian Bandit strategy

Thanks to szeitlin and jcbozonier.

Initial release of slots.
- Basic functionality
- Selection algorithms
- Epsilon greedy
- Softmax
- Upper credibility bound