add some demos & styles

1. add window demo
2. add scrollviewer demo
3. add radiobutton style
4. fixed some bugs
5. add research project

HandyControlDemo/UserControl/Controls/WindowDemoCtl.xaml.cs

@@ -1,4 +1,8 @@
-// ReSharper disable once CheckNamespace
+using System.Windows;
+using HandyControl.Controls;
+using HandyControl.Tools;
+
+// ReSharper disable once CheckNamespace
 namespace HandyControlDemo.UserControl
 {
     public partial class WindowDemoCtl
@@ -7,5 +11,40 @@ namespace HandyControlDemo.UserControl
         {
             InitializeComponent();
         }
+
+        private void ButtonMessage_OnClick(object sender, RoutedEventArgs e)
+        {
+            PopupWindow.ShowDialog(Properties.Langs.Lang.GrowlAsk, showCancel: true);
+        }
+
+        private void ButtonMouseFollow_OnClick(object sender, RoutedEventArgs e)
+        {
+            var picker = SingleOpenHelper.CreateControl<ColorPicker>();
+            var window = new PopupWindow
+            {
+                PopupElement = picker
+            };
+            picker.SelectedColorChanged += delegate { window.Close(); };
+            picker.Canceled += delegate { window.Close(); };
+            window.Show(ButtonMouseFollow, false);
+        }
+
+        private void ButtonCustomContent_OnClick(object sender, RoutedEventArgs e)
+        {
+            var picker = SingleOpenHelper.CreateControl<ColorPicker>();
+            var window = new PopupWindow
+            {
+                PopupElement = picker,
+                WindowStartupLocation = WindowStartupLocation.CenterScreen,
+                AllowsTransparency = true,
+                WindowStyle = WindowStyle.None,
+                MinWidth = 0,
+                MinHeight = 0,
+                Title = Properties.Langs.Lang.ColorPicker
+            };
+            picker.SelectedColorChanged += delegate { window.Close(); };
+            picker.Canceled += delegate { window.Close(); };
+            window.Show();
+        }
     }
 }