Added XML documentation.

DiscImageChef.Devices/Device/Destructor.cs

@@ -42,6 +42,10 @@ namespace DiscImageChef.Devices
 {
     public partial class Device
     {
+        /// <summary>
+        /// Releases unmanaged resources and performs other cleanup operations before the
+        /// <see cref="DiscImageChef.Devices.Device"/> is reclaimed by garbage collection.
+        /// </summary>
         ~Device()
         {
             if (fd != null)