Added dependency injection

imagecatalog/Services/TestService.cs

@@ -0,0 +1,18 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace ImageCatalog_2.Services
+{
+    public interface ITestService
+    {
+
+    }
+
+    public class TestService : ITestService
+    {
+
+    }
+}