refs #575, using livery completer

* embedded in form
* rectified readOnly / only for selection
* added uper case validator where missing
* selecting airline triggers loading of default livery

src/blackgui/editors/form.h

@@ -35,6 +35,10 @@ namespace BlackGui
             //! Set editable
             virtual void setReadOnly(bool readOnly) = 0;
 
+            //! Read only, but entity can be selected (normally used in mapping).
+            //! Use setReadOnly to reset this very state
+            virtual void setSelectOnly() = 0;
+
             //! Is read only?
             bool isReadOnly() const { return m_readOnly; }