message: Add sentence to README
diff: @@ -166,6 +166,9 @@ input(onClick="methodname(\"\" + variable + \"\", this)")
  input(onClick=`methodname("${variable}", this)`)
  ```
  +As mentioned in [pugjs.org Attribute Interpolation](https://pugjs.org/language/attributes.html#attribute-interpolation) (2.),
  +you should prefere ES2015 template strings to simplify your attributes.
  +
  [Issue 54](https://github.com/prettier/plugin-pug/issues/54)
  ```pug
  