New section components no longer get their number on creation. This has 
the effect that the section gets a new number and is updated again with 
all others after that.
Numbering of all sections is triggered in one place (UnitService) and 
updates all existing sections.

This reverts commit 6ddfd7f7.

This makes no sense in expert mode either but is harder to solve. :)

Also add controls to non-expert mode.

Since there is not dimension-tab is this mode, the controls are placed 
here.

Everybody is considered expert but role 'developer'. The host 
application allows not saving the unit when rights are insufficient, so 
the editor needs not to take care of that. Having full rights allows for 
better inspection of units even if it can't be changed(saved).

So they work within standalone dialogs.

This fixes Tables which houses elements without dimensions.

Now always use grabbing when dragging.