meta: docs badge

Author: jtobin

README.md

@@ -2,6 +2,7 @@
 
 [![](https://img.shields.io/hackage/v/ppad-script?color=blue)](https://hackage.haskell.org/package/ppad-script)
 ![](https://img.shields.io/badge/license-MIT-brightgreen)
+[![](https://img.shields.io/badge/haddock-script-lightblue)](https://docs.ppad.tech/script)
 
 Representations for [Script](https://en.bitcoin.it/wiki/Script),
 including abstract syntax, 'ByteArray', and base16-encoded 'ByteString'