Add README badges (#1)

WordPress Playground badge inspired by https://github.com/ndiego/icon-block.

Author: sirreal

README.md

@@ -1,5 +1,7 @@
 # HTML API Debugger
 
+[![Playground Demo](https://img.shields.io/wordpress/plugin/v/html-api-debugger?style=for-the-badge&logo=wordpress&logoColor=%23fff&logoSize=auto&label=Playground%20Demo&labelColor=%233858e9&color=%233858e9)](https://playground.wordpress.net/?blueprint-url=https%3A%2F%2Fraw.githubusercontent.com%2Fsirreal%2Fhtml-api-debugger%2Fmain%2Fassets%2Fblueprints%2Fblueprint.json) [![Downloads](https://img.shields.io/wordpress/plugin/dt/html-api-debugger?style=for-the-badge&logo=wordpress&logoColor=auto)](https://wordpress.org/plugins/html-api-debugger/)
+
 [This is a WordPress plugin to help debug the behavior of the HTML API.](https://wordpress.org/plugins/html-api-debugger/)
 
 [Try it out in the WordPress Playground.](https://playground.wordpress.net/?blueprint-url=https%3A%2F%2Fraw.githubusercontent.com%2Fsirreal%2Fhtml-api-debugger%2Fmain%2Fassets%2Fblueprints%2Fblueprint.json)