Add information about plot sizing to introduction
Add information about plot sizing to introduction

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