Add SteamController implementation

This adds a Steam Shortcuts, Desktop Mode, and X360 Emulation
- Supports all Steam Shortcuts (including on-screen keyboard, and brightness)
- Supports Desktop mode (with a scroll on left pad and left stick), and trackpoint (on right stick)
- Supports X360 mode: hold Options for 1s to switch between Desktop and X360
- Holding Steam button enables Desktop like controls and stops passing all inputs to X360

SteamController/Program.cs

@@ -0,0 +1,21 @@
+namespace SteamController
+{
+    internal static class Program
+    {
+        /// <summary>
+        ///  The main entry point for the application.
+        /// </summary>
+        [STAThread]
+        static void Main()
+        {
+            // To customize application configuration such as set high DPI settings or default font,
+            // see https://aka.ms/applicationconfiguration.
+            ApplicationConfiguration.Initialize();
+
+            using (var controller = new Controller())
+            {
+                Application.Run();
+            }
+        }
+    }
+}