Support for elements besides textarea

This might be a little out there, but I'm trying to build a component that behaves exactly like an autosizing textarea, but *is not* a ``. I need to create a `<div>` with `contenteditable` set so I can use child elements in my editable area.

It'd be awesome if `TextareaAutosize` could support an optional `tag` property that allows the tag to be set, and defaults to `textarea`.

Thanks!