remove using

Author: theClueless

Wox.Infrastructure/Image/ImageLoader.cs

@@ -2,7 +2,6 @@
 using System.Collections.Concurrent;
 using System.IO;
 using System.Linq;
-using System.Threading;
 using System.Threading.Tasks;
 using System.Windows.Media;
 using System.Windows.Media.Imaging;