Automatic merge of T1.6-rc7-38-ge57a7a113 and 14 pull requests

- Pull request #1086 at e10390b: Add Settings Exporter tool (copy settings to INI, etc)
- Pull request #1091 at 2e06f85: Automatic speed control
- Pull request #1104 at 87cdd9f: Handle simple adhesion within the axle module
- Pull request #1115 at 270f22f: Do not activate ETS switch if no suitable cars are attached
- Pull request #1120 at ba3c47f: Automatically Calculate Friction Values if Missing
- Pull request #1121 at 91d2d26: Manually Override Articulation
- Pull request #1130 at 8ae6bb7: Fix F9 points to an incorrect car ID.
- Pull request #1139 at 03c6f8f: Fix for bug https://bugs.launchpad.net/or/+bug/2117357. 
- Pull request #1143 at 71e57d2: Status in Work Orders popup set too fast
- Pull request #1151 at 5e59187: fix: Do not allow non-ACE/DDS textures in content
- Pull request #1082 at 5845a1a: Allow variable water level in glass gauge
- Pull request #1081 at 689494b: Brake cuts power unification
- Pull request #1124 at fab5457: Built-in PBL2 brake controller
- Pull request #1128 at 58de4c3: Particle Emitter Overhaul

Author: openrails-bot

Source/Documentation/Manual/features-rollingstock.rst

@@ -345,7 +345,7 @@ Detailed spec
    no changes are done to the .eng file.
 2) In such folder there is also an ``ORTSLightGlow.png``, which is maybe more realistic.
 3) adding a line within the .eng file it is possible to select either ORTSLightGlow.png or any other picture
-   with extension ``.png, .jpg, bmp, .gif, .ace, or .dds``.
+   with extension ``.ace`` or ``.dds``.
 
 
    Here an example for the legacy Acela loco::
@@ -357,13 +357,13 @@ Detailed spec
 			      Type	( 1 )
 			      Conditions	(...
 
-  The code first searches for the .png file by building its directory starting from the directory of 
+  The code first searches for the file by building its directory starting from the directory of 
   the .eng file; in this case the line could be e.g.::
 
-           ORTSGraphic ( "ORTSAcelaLightGlow.png" )
+           ORTSGraphic ( "ORTSAcelaLightGlow.dds" )
 
 4) The ``ORTSGraphic`` line can be added also for one or more ``Light()`` blocks. In that case the 
-   .png file is used only for the related Light block. Here an example::
+   file is used only for the related Light block. Here an example::
 
     Light	(
 			comment( Head light outer right bright )
@@ -386,7 +386,7 @@ Detailed spec
 					Elevation ( -50 -50 -50 )
 					)
 				)
-			ORTSGraphic (BigLightGlow.png)
+			ORTSGraphic (BigLightGlow.dds)
     )
 
   OR searches for the file as it does for the general file for all lights, as explained above.

Source/RunActivity/Viewer3D/Lights.cs

@@ -988,7 +988,7 @@ public LightGlowMaterial(Viewer viewer, string textureName)
             : base(viewer, textureName)
         {
             // TODO: This should happen on the loader thread.
-            LightGlowTexture = SharedTextureManager.Get(Viewer.RenderProcess.GraphicsDevice, textureName);
+            LightGlowTexture = textureName.StartsWith(Viewer.ContentPath, StringComparison.OrdinalIgnoreCase) ? SharedTextureManager.Get(Viewer.RenderProcess.GraphicsDevice, textureName) : Viewer.TextureManager.Get(textureName);
         }
 
         public override void SetState(GraphicsDevice graphicsDevice, Material previousMaterial)

Source/RunActivity/Viewer3D/MSTSSky.cs

@@ -543,8 +543,8 @@ public MSTSSkyMaterial(Viewer viewer)
                 string mstsSkySunTexture = Viewer.Simulator.RoutePath + @"\envfiles\textures\" + mstsskysatellitetexture[0].TextureName.ToString();
                 string mstsSkyMoonTexture = Viewer.Simulator.RoutePath + @"\envfiles\textures\" + mstsskysatellitetexture[1].TextureName.ToString();
 
-                MSTSSkySunTexture = SharedTextureManager.Get(Viewer.RenderProcess.GraphicsDevice, mstsSkySunTexture);
-                MSTSSkyMoonTexture = SharedTextureManager.Get(Viewer.RenderProcess.GraphicsDevice, mstsSkyMoonTexture);
+                MSTSSkySunTexture = Viewer.TextureManager.Get(mstsSkySunTexture);
+                MSTSSkyMoonTexture = Viewer.TextureManager.Get(mstsSkyMoonTexture);
             }
             else
                 MSTSSkyMoonTexture = SharedTextureManager.Get(Viewer.RenderProcess.GraphicsDevice, System.IO.Path.Combine(Viewer.ContentPath, "MoonMap.png"));