add sample_weight to base score and weight_boosting staged_score
metrics: add sample_weight support
grid_search: add sample_weight support
cross_val_score: add sample_weight support
scorer: add sample_weight support
add sample_weight to learning_curve and rfe
weight_boosting: unneeded np.copy
test_metrics: space after asserts
cross_validation: copy fit_params before adding sample_weight
test_sample_weight_invariance: use fixed seed in random weights
roc_auc_score: implement sample_weight for binary clf
test_metrics: use list for METRICS_WITH_SAMPLE_WEIGHT
sample_weight in average_precision_score
sample_weight in validation_curve