New return a instance of DownloadManager with options.

WithConcurrency set number of concurrent request to be made.

WithFilename set the filename.

WithFilePath set the directory to save file.

WithLogger set custom logger.

WithSkipSubPathMap skip subdirectory resolving.

WithSubPathMap set the directory to save file.

WithVerbose enable debug output log.

DownloadManager ...

Reader represents a custom reader.

HTTPClient interface.

OptionFunc represents a contract for option func, it basically set options to jsonq instance options.