Add github sponsor link on homepage

Author: kpicaza

docs/README.md

@@ -33,6 +33,8 @@ php -S 127.0.0.1:8000 ./public
     <img alt="JetBrains" src="/images/jetbrains-variant-4.png" style="width:263px !important;height:147px !important"/>
 </a>
 
+<iframe src="https://github.com/sponsors/kpicaza/card" title="Sponsor kpicaza" height="225" width="600" style="border: 0;"></iframe>
+
 ###### Disclaimer: 
 
 * This framework is based on concepts and components of other open source software, especially [Laminas Request Handler Runner](https://docs.laminas.dev/laminas-httphandlerrunner/), [Mezzio](https://docs.mezzio.dev/mezzio/) and [Laminas API tools legacy Zend Stratigillity](https://api-tools.getlaminas.org/).