docs(readme): add description and supported languages

Author: SebastiaanYN

README.md

@@ -1 +1,19 @@
 # web-beautify
+
+Beautify languages on the web through web workers.
+
+## Supported languages
+
+- JavaScript
+- TypeScript
+- CSS
+- SCSS
+- Less
+- JSON
+- JSON5
+- GraphQL
+- Markdown
+- HTML
+- Vue
+- YAML
+- PHP