- Use `inputmode` 'none' to hide the virtual keyboard of the os
- Use DeviceService to detect if the player is running
on a mobile device

verticalButtonAlignment is the new property for likert rows, which tells 
the actual radio button to either be at the top or in the middle.

The whole DOM structure is kind of botched. This is a quick fix and 
should be reviewed.

This was causing issues by setting the font size when changing the font 
color. It is probably not useful anyway and removed. Can be repaired and 
introduced when needed.

Also rename LikertColumn to ColumnHeader, since it is not exclusively 
used by likert.

The LikertColumn is actually just an image-text-combo. Has a generalized 
name now.
The other interface was not needed anymore and has been deleted.

- A new new editor component has been created for this, which has a
reduced interface and produces span-elements instead of paragraphs.
- Since the created HTML (span with CSS) is regarded as potentially
harmful it needs to be sanitized. For element components the sanitizer
is put in the abstract parent element-component-directive.

This makes for smaller more managable components.

to ensure that a section that is not displayed has no dimensions

Call emitter in template and remove unnecessary method

Sections use the mediaStatusChanged event, which is also used to map the
interdependence of media elements

This allows showing the contained text in multiple columns.

The material dialog functionality used, adding the mat-dialog-title 
directive the toolbar.

The text area was mistakenly shown.

There were several issues with it's properties, which could not be 
changed.
Now it is properly initialized and prop change get actually handled.

This helps identifying the selected element.

gridColumnStart to gridColumn, for example.