notification service and user management improvements

Oqtane.Client/Services/Interfaces/INotificationService.cs

@@ -0,0 +1,19 @@
+using Oqtane.Models;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+namespace Oqtane.Services
+{
+    public interface INotificationService
+    {
+        Task<List<Notification>> GetNotificationsAsync(int SiteId, string Direction, int UserId);
+
+        Task<Notification> GetNotificationAsync(int NotificationId);
+
+        Task<Notification> AddNotificationAsync(Notification Notification);
+
+        Task<Notification> UpdateNotificationAsync(Notification Notification);
+
+        Task DeleteNotificationAsync(int NotificationId);
+    }
+}