Add image with all seaborn palettes to tutorial
Add image with all seaborn palettes to tutorial

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