private void AddNewSource()
        {
            Console.WriteLine("Please submit a path to file:");
            var path = Console.ReadLine();

            if (!File.Exists(path))
            {
                Console.WriteLine("Path is incorrect. Try again.");
                AddNewSource();
            }

            var res = manager.AddNewSource(path);

            if (!res)
            {
                Console.WriteLine("Adding new file was unsuccessful.");
            }
            else
            {
                Console.WriteLine("File was added successfully.");
                ListSources();
            }
            Start();
        }