Automatic merge of T1.5.1-411-g51d4cd969 and 19 pull requests

- Pull request #570 at de7a14f: Experimental glTF 2.0 support with PBR lighting
- Pull request #757 at d9d75f4: Unify RailDriver code implementations
- Pull request #799 at dc03850: Consolidated wind simulation
- Pull request #802 at 4d198e4: Added support for activity location events to the TrackViewer
- Pull request #803 at 7157e08: Various adjustments to steam adhesion
- Pull request #813 at 7fdad38: Refactored garbage generators
- Pull request #815 at a5cc165: chore: Add GitHub automatic release notes configuration
- Pull request #818 at 0d2162a: Allow independent drive axles for locomotives
- Pull request #821 at e0fa5a8: Adds suppression of safety valves
- Pull request #823 at 5e1c03b: Select track sound volume percent retained in .eng and .wag files
- Pull request #824 at f16ebed: Update Readme.md
- Pull request #825 at 29ed427: 2D Cabview controls for side viewpoints https://blueprints.launchpad.net/or/+spec/2dcabview-controls-for-side-views
- Pull request #829 at 434af02: Improvements for air brakes #3 - Emergency valves
- Pull request #830 at 280ee74: Electric locomotive hot start
- Pull request #831 at c8927a4: preliminary version switchpanel on tablet
- Pull request #832 at bb8941f: Fix Cruise Control together with Train Brake
- Pull request #833 at 01aaca7: Implement brake relay valve
- Pull request #834 at 7a98eca: Replaces email service with FormSpark
- Pull request #835 at 366c96e: Correct Brake Shoe Force Calculation

Author: openrails-bot

Source/Orts.Simulation/Simulation/RollingStocks/SubSystems/Brakes/MSTS/AirSinglePipe.cs

@@ -725,7 +725,7 @@ public override void Update(float elapsedClockSeconds)
                 }
                 else
                 {
-                CylPressurePSI = demandedPressurePSI;
+                CylPressurePSI = Math.Max(demandedPressurePSI, BrakeLine3PressurePSI);
             }
 
             // During braking wheelslide control is effected throughout the train by additional equipment on each vehicle. In the piping to each pair of brake cylinders are fitted electrically operated