public ActionResult DeleteComment(Comment comment)
        {
            db.Entry(comment).State = System.Data.EntityState.Deleted;
            db.SaveChanges();

            return RedirectToAction("Posts");
        }
        public ActionResult Comment(Comment comment)
        {
            var user = db.Users.Where(e => e.UserName == HttpContext.User.Identity.Name).FirstOrDefault();
            comment.CommentDateTime = DateTime.Now;
            comment.UserId = user.Id;

            db.Entry(comment).State = System.Data.EntityState.Added;
            db.SaveChanges();

            return RedirectToAction("Posts");
        }