docs: add Patreon link

Author: Akryum

README.md

@@ -5,6 +5,16 @@
 
 Smooth scroll with any amount of data ([demo](https://akryum.github.io/vue-virtual-scroller/)).
 
+<p>
+  <a href="https://www.patreon.com/akryum" target="_blank">
+    <img src="https://c5.patreon.com/external/logo/become_a_patron_button.png" alt="Become a Patreon">
+  </a>
+</p>
+
+<br>
+<br>
+<br>
+
 ## Table of contents
 
 - [Installation](#installation)