implement WindowManager, BrowserWindow-API and Menu-API

ElectronNET.API/BrowserWindow.cs

@@ -0,0 +1,16 @@
+namespace ElectronNET.API
+{
+    public class BrowserWindow
+    {
+        public int Id { get; private set; }
+
+        internal BrowserWindow(int id) {
+            Id = id;
+        }
+
+        public void Minimize()
+        {
+            BridgeConnector.Socket.Emit("browserWindow-minimize", Id);
+        }
+    }
+}