unify enable/disable features by docking widgets

[ReimarBauer]

Any docking widget has its own button wording for removing its information.

• WMS: remove
• KML: deactivate selected file
• satellite track: no idea
• remote sensing: no idea
• Airport / Airspaces: deactivate selected items

We should create a template with a few rules which can be used to create a docking widget.e.g.

• disable what this docking widget does on the view where it is used.
• enable what this docking widget does
• lock changes (none of them have this currently)