Optimizing panel views

As a user, I will keep focus of a panel's content when scrolling inside of another one, that is: the other views should be fixed.

Ideas:

• The panels should make use of the max screen size (should be oriented at the different screensizes S, M, L responsisivenes)
• The area inside the panel should be scrollable
• The scrollbars shouldn't be displayed
• By default the Treeview should always focus the actual item selected (which has been chosen by the user; either via knot or via Navbutton)
• fix the panel tool icons during scrolling
• the knot should open by clicking the title (select property)

related: viewer#29 (moved)