implement full Tray-API

ElectronNET.API/Entities/DisplayBalloonOptions.cs

@@ -0,0 +1,9 @@
+namespace ElectronNET.API
+{
+    public class DisplayBalloonOptions
+    {
+        public string Icon { get; set; }
+        public string Title { get; set; }
+        public string Content { get; set; }
+    }
+}

ElectronNET.API/Entities/HighlightMode.cs

@@ -0,0 +1,20 @@
+namespace ElectronNET.API.Entities
+{
+    public enum HighlightMode
+    {
+        /// <summary>
+        /// Highlight the tray icon when it is clicked and also when its context menu is open. This is the default.
+        /// </summary>
+        selection,
+
+        /// <summary>
+        /// Always highlight the tray icon.
+        /// </summary>
+        always,
+
+        /// <summary>
+        /// Never highlight the tray icon.
+        /// </summary>
+        never
+    }
+}

ElectronNET.API/Entities/TrayClickEventArgs.cs

@@ -0,0 +1,10 @@
+namespace ElectronNET.API
+{
+    public class TrayClickEventArgs
+    {
+        public bool AltKey { get; set; }
+        public bool ShiftKey { get; set; }
+        public bool CtrlKey { get; set; }
+        public bool MetaKey { get; set; }
+    }
+}