Ref T261, detect gnd.flag (from network) suppport, display gnd.flag info in UI

* add flag info in simulated aircraft
* allow to display info  in UI
* unified naming to "contains" in situation list
* updated client provider

src/blackmisc/aviation/aircraftsituation.h

@@ -171,6 +171,12 @@ namespace BlackMisc
             //! Is on ground?
             bool isOnGround() const { return this->getOnGround() == OnGround; }
 
+            //! On ground by parts?
+            bool isOnGroundFromParts() const;
+
+            //! On ground by network flag?
+            bool isOnGroundFromNetwork() const;
+
             //! On ground?
             const QString &onGroundAsString() const;