Support multiline input in UI.getInputFromUser
It would be great for this plugin I wrote, where a single line input is clearly not cutting it : )

<img width="532" alt="Screen Shot 2019-04-04 at 10 34 44" src="https://user-images.githubusercontent.com/3832/55552413-92132480-56dd-11e9-8f49-d85d06315901.png">
