Removed codeblocks as they are only needed on the blog website.
* More stable handling of nested elements. Instead of keeping track of
dragOverElements in a list, the related target of the event is used to
determine if it is an event that happened on the main element or bubbled
up from child elements.
* Fix a bug in drag emulation that occurred when a nested HTML element
was dragged. Getting the element under the drag image was wrong.