This change mainly helps the editor.
The idea is to make the element components have the correct value of
their model and don't rely on the formcontrol value. The formcontrol
can be hard to manipulate, especially in compound elements. Setting
the model value is way easier.

The formcontrols are kept and should not interfere.

There were some things missing when renaming questions/answers to 
rows/columns. Now everything is properly named.

For elements which don't have this functionality the workaround is to 
use pointer events and make the elements unclickable.