Automatic merge of T1.5.1-905-gaf8fb30c5 and 15 pull requests

- Pull request #570 at 3539862: Experimental glTF 2.0 support with PBR lighting
- Pull request #839 at d00beb9: First phase of https://blueprints.launchpad.net/or/+spec/additional-cruise-control-parameters
- Pull request #876 at f92de76: docs: add source for documents previously on website to source Documentation folder
- Pull request #882 at a057eff: Blueprint/train car operations UI window
- Pull request #885 at 8f94333: feat: Add notifications to Menu
- Pull request #886 at 6c0785b: Scene viewer extension to TrackViewer
- Pull request #892 at 1f5ba4c: Signal Function OPP_SIG_ID_TRAINPATH
- Pull request #896 at 5866028: First implementation of https://blueprints.launchpad.net/or/+spec/specific-sounds-for-ai-trains
- Pull request #903 at 9bead33: Downloading route content (Github, zip)
- Pull request #911 at 6834af0: docs: Add refactoring as a special type of PR
- Pull request #916 at 992cc97: Distributed Power Air Brake Synchronization
- Pull request #919 at 9358732: Added mouse wheel support for controls which can be moved by pressing t…
- Pull request #920 at a94e403: Update RailDriver in Manual
- Pull request #923 at d0208cd: Add curve squeal to route
- Pull request #924 at 6c2c3cd: Default Asset Improvements

Author: openrails-bot

Source/RunActivity/Viewer3D/Cameras.cs

@@ -1296,7 +1296,7 @@ protected override void OnActivate(bool sameCamera)
                 isVisibleTrainCarViewerOrWebpage = Viewer.TrainCarOperationsViewerWindow.Visible || (Viewer.TrainCarOperationsWebpage.Connections > 0 && Viewer.TrainCarOperationsWebpage.TrainCarSelected);
             }
 
-            if (attachedCar == null || attachedCar.Train != Viewer.SelectedTrain || carPosition != oldCarPosition || isDownCameraOutsideFront || isDownCameraOutsideRear)
+            if (attachedCar == null || attachedCar.Train != Viewer.SelectedTrain || carPosition != oldCarPosition)
             {
                 if (Front)
                 {