Support copy entries from resource string table

ILSpy/Controls/ResourceStringTable.xaml

@@ -1,13 +1,14 @@
 <?xml version="1.0" encoding="utf-8"?>
 <UserControl
-	x:Class="ICSharpCode.ILSpy.Controls.ResourceStringTable" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:controls="clr-namespace:ICSharpCode.ILSpy.Controls">
+	x:Class="ICSharpCode.ILSpy.Controls.ResourceStringTable" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
 	<UserControl.CommandBindings>
 	<CommandBinding Command="ApplicationCommands.Copy"
 					Executed="ExecuteCopy"
 					CanExecute="CanExecuteCopy"/>
 	</UserControl.CommandBindings>
 	<ListView
-		Name="resourceListView">
+		Name="resourceListView"
+		SelectionMode="Extended">
 		<ListView.View>
 			<GridView
 				AllowsColumnReorder="False">

ILSpy/Controls/ResourceStringTable.xaml.cs

@@ -35,10 +35,12 @@ namespace ICSharpCode.ILSpy.Controls
 		
 		void ExecuteCopy(object sender, ExecutedRoutedEventArgs args)
 		{
-			if (resourceListView.SelectionMode == SelectionMode.Single)
-				return;
-			else if (resourceListView.SelectionMode == SelectionMode.Multiple)
-				return;
+		  StringBuilder sb = new StringBuilder();
+		  foreach (var item in resourceListView.SelectedItems)
+		  {
+		    sb.AppendLine(item.ToString());
+		  }
+		  Clipboard.SetText(sb.ToString());
 		}
 		
 		void CanExecuteCopy(object sender, CanExecuteRoutedEventArgs args)