DragAndDropValueObjects are now a sub-interface of TextImageLabel, which 
requires a set imgSrc and imgPosition property. (The reason is that the 
editor needs a way of generating Labels therefore needs the imgSrc set 
to something else but undefined.)

- Use done event of keyboard animation to set the scroll position
of the element
- In small browser views elements are scrolled to the top of the view
instead of the middle of the view

- no event for elements
- only one event für presented pages

- Fix related tests

This way elements can handle their logic themselves without having to
rely on outside utility classes.

Also restructure files in common in a more logical way.

This facilitates the testability

This marks the end of the test according to the expect method

Rename some test-files