scorer: add sample_weight support
ENH add label ranking average precision
DOC write narrative doc for label ranking average precision
DOC FIX error + wording
TST invariance testing + handle degenerate case
flake8
FIX use np.bincount
DOC friendlier narrative documentation
ENH simplify label ranking average precision (thanks @jnothman)
ENH be backward compatible for old version of scipy
Typo
pep8
DOC remove confusing mention to mean average precision
DOC improve documentatino thanks to @vene and remove mention of relevant labels
FIX: Remove raw_coef_ attribute that eats up memory
Modified sparse OvR to handle sparse target data

Defaulted label binarizer to set sparse_output=True when training ovr
classifiers, edited Label binarizer to allow for sparse binary column output
DOC fix docstrings; add @hamsal to authors
split test_common.py into checks and test file.
move dataset generation into estimator_checks
Remove 'DeprecationWarning: using a non-integer number instead of an integer will result in an error in the future' warnings
Closes #2360. Fix tiebreaking.