Add new and correct existing fns in DataTransfer

[japgolly]

No description provided.

[sjrd]

What spec did you use? I see http://www.w3.org/html/wg/drafts/html/master/editing.html#the-datatransfer-interface and there are discrepancies.

[japgolly]

https://developer.mozilla.org/en-US/docs/Web/API/DataTransfer

[sjrd]

Hum ... is there some evidence that addElement is supported by other browsers? Is this a Firefox-only thing? Why would it appear in MDN but not in the spec? Wand why, why doesn't MDN reference the spec it bases itself on, as it usually does?

Regardless, I would stick to format instead of type for the parameter names. Since there two contradicting names, let's keep the Scala-friendly one ;)

[japgolly]

Woah, so in 2011 they dropped it from the spec (http://lists.w3.org/Archives/Public/public-webapps/2011OctDec/0171.html) but for some reason MDN/Firefox has kept it around.

Ok I've removed it changed type back to format as requested. Should be good now.

[sjrd]

LGTM, thanks.