ENH: Call plot twice per class label rather than for every point.
ENH: Call plot twice per class label rather than for every point.
Merge branch 'plot_dbscan' of https://github.com/ericjster/scikit-learn into plot_dbscan

Fix formatting to be PEP8.
Merge pull request #2502 from ericjster/plot_dbscan

ENH: Call plot twice per class label rather than for every point.