Ardalis/upgrade1 (#44)

* Upgrading to netcore 2.0
Updating repository to support async options and refactoring to use it.

* Starting work on tracking customer orders feature.

* Cleaning up some bugs
Working on basket view component implementation

* Fixing up styles, especially for basket in header.

src/Web/ViewComponents/Basket.cs

@@ -0,0 +1,27 @@
+using ApplicationCore.Interfaces;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.eShopWeb.ViewModels;
+using System.Threading.Tasks;
+
+namespace Web.ViewComponents
+{
+    public class Basket : ViewComponent
+    {
+        private readonly IBasketService _cartSvc;
+
+        public Basket(IBasketService cartSvc) => _cartSvc = cartSvc;
+
+        public async Task<IViewComponentResult> InvokeAsync(string userName)
+        {
+            var vm = new BasketComponentViewModel();
+            var itemsInCart = await ItemsInBasketAsync(userName);
+            vm.ItemsCount = itemsInCart;
+            return View(vm);
+        }
+        private async Task<int> ItemsInBasketAsync(string userName)
+        {
+            var basket = await _cartSvc.GetOrCreateBasketForUser(userName);
+            return basket.Items.Count;
+        }
+    }
+}