add some demos & styles

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

DockContainerResearch/MainWindow.xaml

@@ -0,0 +1,12 @@
+<Window x:Class="DockBoxResearch.MainWindow"
+        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+        xmlns:controls="clr-namespace:DockBoxResearch.Controls"
+        mc:Ignorable="d"
+        Title="MainWindow" Height="450" Width="800">
+    <controls:DockBox>
+        
+    </controls:DockBox>
+</Window>