readme upd

Author: rasbt

README.md

@@ -13,8 +13,9 @@ This project is not connected to the gallery on [http://matplotlib.org/gallery.h
 - [Bar plots](#bar-plots)
 - [Boxplots and Violinplots](#boxplots-and-violinplots)
 - [Errorbar plots](#errorbar-plots)
-- [Formatting I: subplots, markers, colors, axes](#formatting-i)
-- [Formatting II: gridlines](#formatting-i)
+- [Formatting I: subplots, markers, colors, axes](#formatting-i-subplots-markers-colors-axes)
+- [Formatting II: gridlines](#formatting-ii-gridlines)
+- [Formatting III: legends](#formatting-iii-what-it-takes-to-become-a-legend)
 - [Histograms](#histograms)
 - [Line plots](#line-plots)
 - [Preparing Plots for Publication](#preparing-plots-for-publication)