message: Add list of API methods in example usage section in README
diff: @@ -171,10 +171,24 @@ Classname that will be applied to the wrapper when a pointer is dragging the car
  ## API
  -Embla exposes a set of methods upon setup that can be used to control the carousel externally. Example usage looks like this...
  +Embla exposes a set of methods upon setup that can be used to control the carousel externally. Usage looks like this:
  ```javascript
  +embla.containerNode()
  +embla.slideNodes()
  embla.next()
  +embla.previous()
  +embla.goTo(2)
  +embla.selectedIndex()
  +embla.previousIndex()
  +embla.groupedIndexes()
  +embla.isFirstIndex()
  +embla.islastIndex()
  +embla.hasPreviousIndex()
  +embla.hasNextIndex()
  +embla.changeOptions({ loop: true })
  +embla.on('select', () => console.log('Selected a new index!'))
  +embla.destroy()
  ```
  ...and the methods are:
  