#706

#702

#704

This service is unused for a long time.

Now the paragraphs are shown actually below each other and not next to.

#699

For automatic numbering of droplist items another node level 
(div-element) was introduced to the element DOM. Therefore this 
functions needs to look another node further up for it's position.

#694

- Image
- Hotspot-Image
- Audio
- Video
- Geometry
- DragNDropValueObject (imgFileName, audioFileName)
- LikertRowElement (imgFileName, audioFileName)

Just ignore the color in the component.

- editor and player have their own services to handle the errors

- remove 'own' as possible connection

- to allow the display properties to be overwritten

- remove 'none'

Also refactor a lot of stuff around the page canvas and unit view.

#684

Also add separate file to handle drop-logic.

#671