Construct all methods from scikit classifiers

[wmkouw]

A couple of people have sent emails that they expected certain scikit methods to be present, e.g. predict_proba.

Plan is to make sure that all my classifiers have at least:

• [x] fit(X, y[, sample_weight])
• [ ] get_params([deep])
• [x] predict(X)
• [ ] predict_log_proba(X)
• [ ] predict_proba(X)
• [ ] score(X, y[, sample_weight])
• [ ] set_params(**params)

Or throw an exception that a particular functionality is not possible.