Feature request: Add support for input type file

[akshaybabloo]

It would be great to have a Paper-dashboard support for <input type="file" class="form-control">.

As of now it is rendering it as

Something like https://www.abeautifulsite.net/whipping-file-inputs-into-shape-with-bootstrap-3 would be nice.

[alexandru-paduraru]

@akshaybabloo thank you for the suggestion, we will add it in the next release. Till then we recommend you this library: http://www.jasny.net/bootstrap/javascript/#fileinput

It should look fine with our current style.

Best,
Alex