Twenty Eleven: Provide support for global HTML 5 form elements

[mfields]

When a plugin is used to render a form in the content area only basic support is provided for styling. Certain inputs like email tend to stick out:

I think it would be a good idea to introduce support for password, input, and email as seen in Twenty Eleven.

[helenyhou]

#20579

[lancewillett]

In 22898:

Twenty Eleven: style a few more common input types. See #20579 and #21757.