Update README.md remove outdated donation tab

Author: mcm1957

README.md

@@ -2,8 +2,6 @@
 # ioBroker.nuki-extended
 This ioBroker adapter (formerly ioBroker.Nuki2) allows to control and monitor the [Nuki Smart Lock](https://nuki.io/de/smart-lock/) and / or the [Nuki Opener](https://nuki.io/de/opener/) by using both the [Nuki Bridge API (v1.9.0, 06.05.2019)](https://developer.nuki.io/page/nuki-bridge-http-api-170/4/#heading--introduction) and the [Nuki Web API (v1.2.0, 31.05.2019)](https://developer.nuki.io/page/nuki-web-api-111/3/).
 
-[![Paypal Donation](https://img.shields.io/badge/paypal-donate%20|%20spenden-blue.svg)](https://paypal.me/chvoelkel)
-
 ![Number of Installations](http://iobroker.live/badges/nuki-extended-installed.svg)
 ![Number of Installations](http://iobroker.live/badges/nuki-extended-stable.svg)
 [![NPM version](http://img.shields.io/npm/v/iobroker.nuki-extended.svg)](https://www.npmjs.com/package/iobroker.nuki-extended)