Code modernising (#8)

* Applied some code conventions, used more current language features which should improve readability and making it easier to re-factor / modify. Also fixed some typos in documentation.
* Changes based on PR conversation for the SystemInfo
* Some modifications due to conversations on the PR, especially I removed the FlagsAttribute on the BalloonFlags.
* Removed Silverlight targeting in code.

Hardcodet.NotifyIcon.Wpf/Source/WindowsFormsSample/FancyPopup.xaml.cs

@@ -13,7 +13,7 @@ namespace Samples
         /// The number of clicks on the popup button.
         /// </summary>
         public static readonly DependencyProperty ClickCountProperty =
-            DependencyProperty.Register("ClickCount",
+            DependencyProperty.Register(nameof(ClickCount),
                 typeof (int),
                 typeof (FancyPopup),
                 new FrameworkPropertyMetadata(0));

Hardcodet.NotifyIcon.Wpf/Source/WindowsFormsSample/Program.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Windows.Forms;
-using Samples;
 
 namespace WindowsFormsSample
 {

Hardcodet.NotifyIcon.Wpf/Source/WindowsFormsSample/Properties/AssemblyInfo.cs

@@ -1,6 +1,4 @@
-using System.Reflection;
-using System.Runtime.CompilerServices;
-using System.Runtime.InteropServices;
+using System.Runtime.InteropServices;
 
 // Setting ComVisible to false makes the types in this assembly not visible 
 // to COM components.  If you need to access a type in this assembly from