Refactored repository pattern for Add and Update methods so that they return their respective entity objects

Oqtane.Server/Repository/IUserRepository.cs

@@ -6,8 +6,8 @@ namespace Oqtane.Repository
     public interface IUserRepository
     {
         IEnumerable<User> GetUsers();
-        void AddUser(User User);
-        void UpdateUser(User User);
+        User AddUser(User User);
+        User UpdateUser(User User);
         User GetUser(int UserId);
         User GetUser(string Username);
         void DeleteUser(int UserId);