Automatic merge of T1.6-106-gdcc176472 and 13 pull requests

- Pull request #1156 at f46d5f2: Fix incorrectly disabled options in train operations window
- Pull request #1091 at 492795a: Automatic speed control
- Pull request #1120 at ba3c47f: Automatically Calculate Friction Values if Missing
- Pull request #1121 at 91d2d26: Manually Override Articulation
- Pull request #1124 at e241a0d: Built-in PBL2 brake controller
- Pull request #1157 at 39cd994: Dynamic brake authorization by TCS
- Pull request #1159 at 48c9a63: Skip OR warnings about TSRE-specific token Ruler
- Pull request #1161 at 6cfe4e2: Fix string trim in .ini files
- Pull request #1162 at 2516cce: specifies precedence of DDS over ACE
- Pull request #1163 at 2f9e292: Fix: Crash when using Camera 8 and F9.
- Pull request #1082 at 5845a1a: Allow variable water level in glass gauge
- Pull request #1128 at 086d502: Particle Emitter Overhaul
- Pull request #1160 at 9dc6b3b: Route Based TTrack Sounds

Author: openrails-bot

Source/RunActivity/Viewer3D/Popups/TrainCarOperationsWindow.cs

@@ -644,7 +644,7 @@ public override void PrepareFrame(ElapsedTime elapsedTime, bool updateFull)
                 }
 
                 // Restore LastCarIDSelected (F9) after returning from different camera views
-                if (CarIdClicked && Owner.Viewer.Camera.AttachedCar.CarID != LastCarIDSelected)
+                if (CarIdClicked && Owner.Viewer.Camera.AttachedCar != null && Owner.Viewer.Camera.AttachedCar.CarID != LastCarIDSelected)
                 {
                     trainCarViewer.CurrentCarID = LastCarIDSelected;
                     trainCarViewer.CarPosition = CarPosition = PlayerTrain.Cars.TakeWhile(x => x.CarID != LastCarIDSelected).Count();
@@ -788,7 +788,7 @@ public FormationReversed(Viewer viewer, Train PlayerTrain)
             Viewer = viewer;
             TrainCar = Viewer.TrainCarOperationsWindow;
             TrainCarViewer = Viewer.TrainCarOperationsViewerWindow;
-            var currentCameraCarID = Viewer.Camera.AttachedCar.CarID;
+            var currentCameraCarID = Viewer.Camera.AttachedCar != null ? Viewer.Camera.AttachedCar.CarID : TrainCar.LastCarIDSelected;
 
             TrainCarViewer.CurrentCarID = TrainCar.LastCarIDSelected;
             TrainCarViewer.CarPosition = TrainCar.CarPosition = PlayerTrain.Cars.TakeWhile(x => x.CarID != TrainCar.LastCarIDSelected).Count();