Add isMultiline to <ContentEditable/>

[theMasix]

I had a problem and it solved by #150. I think it would be great if the ContentEditable component accepts something like isMultiline and if it's set to false, then some validation happens and tabs or line break doesn't allow anymore.

[joseDaKing]

You could just use onKeyDown and check if event.key is "Enter" and then prevent default

Here is a link to the sandbox