Number type doesn't change input box to type number

Hi Brad,

Great plugin, we’re using it for a submission form for mobile.

I noticed one small bug that would be great if it was fixed in the next version:

When you change the custom field type to “number” it doesn’t actually change the input box on the front end to type=”number”.. it stays as type=”text” which means on mobile it pops up a full keyboard, not a number pad.

Thanks again for the great plugin.
Josh