don't enforce DTYPE at the ensemble level
DOCS: note generator behaviour in staged methods
TEST: make test_importances more stable
DOC: narrative documentation
DOC: What's new
TEST: base_estimator
DOC: classes_ and n_classes_
DOC: put docstrings into subclasses to make them appear in the documentation
rename learn_rate -> learning_rate
raise ValueError if len(y_true) is less than or equal to 1
add some tests for weighted_r2_score
DOC + Better default parameter values
DOC: cosmits
DOC: typo
PEP8 and DOC
ENH: use shuffle
Make BaseWeightBoosting abstract and other misc changes
Roll back some changes
Roll back some changes (2)
FIX: what's new
ENH common test that set_params returns self.