Created and implemented StockDal.InterFace

StockDal.Interface/IProductRepository.cs

@@ -0,0 +1,14 @@
+using StockDomain;
+using System;
+using System.Collections.Generic;
+
+namespace StockDal.Interface
+{
+    public interface IProductRepository
+    {
+        IEnumerable<Product> GetProducts();
+        bool Insert(Product product);
+        bool Update(Product product);
+        bool Delete(string productId);
+    }
+}