* Readme update. (#519)

Author: megax

README.md

@@ -1,6 +1,6 @@
 ## Numix
 ##### A modern flat theme with a combination of light and dark elements. It supports GNOME, Unity, Xfce and Openbox.
-[![By The Numix Project](https://img.shields.io/badge/By-The%20Numix%20Project-red.svg?style=flat-square)](https://numixproject.org/)  [![Circle CI](https://img.shields.io/circleci/project/numixproject/numix-gtk-theme/master.svg?circle-token=b14acf911433d315298235b0c2fbf7b2670a92a8&maxAge=2592000&style=flat-square)](https://circleci.com/gh/numixproject/numix-gtk-theme/tree/master)  ![Supports GTK+ 3.16](https://img.shields.io/badge/GTK%2B-3.16-blue.svg?style=flat-square)  ![Supports GTK+ 3.20](https://img.shields.io/badge/GTK%2B-3.20-blue.svg?style=flat-square)
+[![By The Numix Project](https://img.shields.io/badge/By-The%20Numix%20Project-red.svg?style=flat-square)](https://numixproject.org/)  [![Circle CI](https://img.shields.io/circleci/project/numixproject/numix-gtk-theme/master.svg?circle-token=b14acf911433d315298235b0c2fbf7b2670a92a8&maxAge=2592000&style=flat-square)](https://circleci.com/gh/numixproject/numix-gtk-theme/tree/master)  ![Supports GTK+ 3.18](https://img.shields.io/badge/GTK%2B-3.18-blue.svg?style=flat-square)  ![Supports GTK+ 3.20](https://img.shields.io/badge/GTK%2B-3.20-blue.svg?style=flat-square)
 
 ### Manual installation