Move the drag and drop code

[sophiedeziel]

Should we un-deprecate the drag and drop option?

The _enableDropHandler() method could be moved outside of WebGLPreview.

[remcoder]

I'd be for undeprecating DnD. We could probably use something like a a dom-utils module or canvas wrapper class to organize things like DnD and resizing.

[remcoder]

petition to rename 'allowDragNDrop' to dnd. So you can just set the option dnd : true..

or another option: droppable: true.

[sophiedeziel]

I vote droppable!

I'm not a fan of using acronyms in APIs, unless documentation is using the long form. The thing is, even when an acronym is widely known, someone may need to google it to know what it means. I18n is easy to find the meaning for, but dnd could mean a lot of things.