Unit tests working; added logger adapter.

src/ApplicationCore/Interfaces/IAppLogger.cs

@@ -0,0 +1,7 @@
+namespace ApplicationCore.Interfaces
+{
+    public interface IAppLogger<T>
+    {
+        void LogWarning(string message, params object[] args);
+    }
+}

src/ApplicationCore/Interfaces/IImageService.cs

@@ -1,16 +1,7 @@
-using ApplicationCore.Entities;
-using Microsoft.eShopWeb.ApplicationCore.Entities;
-using System.Security.Principal;
-using System.Threading.Tasks;
-
-namespace ApplicationCore.Interfaces
+namespace ApplicationCore.Interfaces
 {
-
     public interface IImageService
     {
         byte[] GetImageBytesById(int id);
     }
-
-
-
 }