Don't label clustermap colors when Series has no name (closes #1177)
Don't label clustermap colors when Series has no name (closes #1177)

sauliusl/seaborn,arokem/seaborn,lukauskas/seaborn,anntzer/seaborn,mwaskom/seaborn,petebachant/seaborn,lukauskas/seaborn,phobson/seaborn,phobson/seaborn,arokem/seaborn,anntzer/seaborn,mwaskom/seaborn