Fixing bug in detaching placeholders.
Fixing bug in detaching placeholders.

lukasoppermann/html5sortable,xiwc/html5sortable,nazar-pc/html5sortable,voidberg/html5sortable,illsism/html5sortable,nazar-pc/html5sortable,illsism/html5sortable,lukasoppermann/html5sortable,xiwc/html5sortable,voidberg/html5sortable,lukasoppermann/html5sortable