Update README.md [skip ci]

Author: JaZo

README.md

@@ -2,7 +2,7 @@
 
 [![Greenkeeper badge](https://badges.greenkeeper.io/swisnl/jQuery-contextMenu.svg)](https://greenkeeper.io/)
 
-[![Travis](https://img.shields.io/travis/swisnl/jQuery-contextMenu/master.svg?style=flat-square&maxAge=600)](https://travis-ci.org/swisnl/jQuery-contextMenu) [![npm](https://img.shields.io/npm/v/jquery-contextmenu.svg?style=flat-square&maxAge=600)](https://www.npmjs.com/package/jquery-contextmenu) [![npm](https://img.shields.io/npm/dm/jquery-contextmenu.svg?style=flat-square&maxAge=600)](https://www.npmjs.com/package/jquery-contextmenu) [![CDNJS](https://img.shields.io/cdnjs/v/jquery-contextmenu.svg?style=flat-square&maxAge=600)](https://cdnjs.com/libraries/jquery-contextmenu) [![npm](https://img.shields.io/npm/l/jquery-contextmenu.svg?style=flat-square)]()
+[![Travis](https://img.shields.io/travis/swisnl/jQuery-contextMenu/master.svg?style=flat-square&maxAge=600)](https://travis-ci.org/swisnl/jQuery-contextMenu) [![npm](https://img.shields.io/npm/v/jquery-contextmenu.svg?style=flat-square&maxAge=600)](https://www.npmjs.com/package/jquery-contextmenu) [![npm](https://img.shields.io/npm/dm/jquery-contextmenu.svg?style=flat-square&maxAge=600)](https://www.npmjs.com/package/jquery-contextmenu) [![CDNJS](https://img.shields.io/cdnjs/v/jquery-contextmenu.svg?style=flat-square&maxAge=600)](https://cdnjs.com/libraries/jquery-contextmenu) [![npm](https://img.shields.io/npm/l/jquery-contextmenu.svg?style=flat-square)]() [![Buy us a tree](https://img.shields.io/badge/Treeware-%F0%9F%8C%B3-lightgreen.svg?style=flat-square)](https://plant.treeware.earth/swisnl/jQuery-contextMenu)
 
 $.contextMenu is a management facility for - you guessed it - context menus. It was designed for an application where there are hundreds of elements that may show a context menu - so intialization speed and memory usage are kept fairly small. It also allows to register context menus without providing actual markup, as $.contextMenu generates DOMElements as needed.
 
@@ -100,6 +100,8 @@ Besides the obvious, browser also react to alphanumeric key strokes. Hitting <co
 
 $.contextMenu is published under the [MIT license](http://www.opensource.org/licenses/mit-license)
 
+This package is [Treeware](https://treeware.earth). If you use it in production, then we ask that you [**buy the world a tree**](https://plant.treeware.earth/swisnl/jQuery-contextMenu) to thank us for our work. By contributing to the Treeware forest you’ll be creating employment for local families and restoring wildlife habitats.
+
 
 ## Special thanks