ENH vectorize DBSCAN implementation
ENH sparse support in DBSCAN
ENH support weighted samples in DBSCAN
FIX DBSCAN.fit_predict now also supports sample_weight
DOC/COSMIT clean up according to review
Merge pull request #3994 from jnothman/vec_dbscan

[MRG+1] DBSCAN: faster, weighted samples, and sparse input