/// <summary>
        ///     Add a logger and limit which classes that can log to it.
        /// </summary>
        /// <param name="logger">Logger to use.</param>
        /// <param name="filter">Filter that logging types must pass.</param>
        public void Add(ILogger logger, ILoggerFilter filter)
        {
            if (logger == null) throw new ArgumentNullException("logger");
            if (filter == null) throw new ArgumentNullException("filter");

            _loggers.Add(new Tuple<ILoggerFilter, ILogger>(filter, logger));
        }
        /// <summary>
        ///     Add a logger and limit which classes that can log to it.
        /// </summary>
        /// <param name="logger">Logger to use.</param>
        /// <param name="filter">Filter that logging types must pass.</param>
        public void Add(ILogger logger, ILoggerFilter filter)
        {
            if (logger == null)
            {
                throw new ArgumentNullException("logger");
            }
            if (filter == null)
            {
                throw new ArgumentNullException("filter");
            }

            _loggers.Add(new Tuple <ILoggerFilter, ILogger>(filter, logger));
        }