Add prop to add `data-` properties to input fields

[nandastone]

I recently needed to add data- properties to the output text and password fields.

This PR adds a prop for doing just that.

[nandastone]

Following these instructions for syncing my fork with your latest master: https://help.github.com/articles/syncing-a-fork/

Any idea why all my previous commits are being re-included in the history of this PR?