public MindboxMappingSource(MindboxMappingConfiguration configuration)
        {
            if (configuration == null)
            {
                throw new ArgumentNullException("configuration");
            }

            if (!configuration.IsFrozen)
            {
                configuration.Freeze();
            }
            Configuration = configuration;
        }
        public MindboxMappingSource(MindboxMappingConfiguration configuration, bool isDatabaseMigrated)
        {
            if (configuration == null)
            {
                throw new ArgumentNullException("configuration");
            }

            if (!configuration.IsFrozen)
            {
                configuration.Freeze();
            }
            Configuration      = configuration;
            IsDatabaseMigrated = isDatabaseMigrated;
        }