Set defaults for CabControls

These will be mostly overridden when parsing the CVF file but allows for controls that don't set during parsing.

Author: Chris Jakeman

Source/Orts.Formats.Msts/CabViewFile.cs

@@ -346,8 +346,10 @@ public class CabViewControl
         public double Width;
         public double Height;
 
-        public double MinValue;
-        public double MaxValue;
+        // Defaults which may be overridden when parsing CVF file
+        public double MinValue = 0.0;
+        public double MaxValue = 1.0;
+        
         public double OldValue;
         public string ACEFile = "";