Make resize optional + allow setting draggable axis

[mikebannister]

Hi,

I have a fork of this with a boolean setting called 'viewport_resize' that allows me to turn off resizing.

My fork also allows passing in an option called draggable_axis which passes on the value to draggable (we only allow some images to move up and down).

Want pull requests for each (or either of these?

Thanks,
Mike

[trepmag]

Hello, of course make the pull request!

Cedric