aria2/TODO

* Add HTTP POST support
* Add expires handling for Cookie
* Add SSL server cert verification
* Add SSL client cert support
* Better HTTP status handling
* Download files listed in a specifed file.
* Add the feature which adds or removes URLs on-the-fly.
* Add port range command-line option
* Add max peers command-line option
* Refacturing HttpConnection and FtpConnection
* Query resource by location
* List available os, version, etc for metalink
* ipv6(RFC2428 for ftp)
* Add silent mode.
* Save URLs and command-line arguments to .aria2 file.
* Add a control port for GUI frontend
* Add a version header to .aria2 file to check the compatibiliy.
* Use SharedHandle where it is useful.
* Rewrite Util::countBit
* Add --bt-timeout command line option.
* Fix DefaultBtProgressInfoFile.cc: save(), load()
* remove blockIndex
* Add seed mode.
* Make trakcerwatchercommand and trackerUploadCommand posses requestGroup 
* consider life cycle of requestGroup and segmentMan
* exit status: all downloads have been successful-> EXIT_SUCCESS,
		some of downloads have been failed -> EXIT_FAILURE


* Create directory structure before initAndOpen:
	HttpResponseCommand.cc
	RequestGroup.cc
	TorrentRequestInfo.cc: <- not the case
* Add ETA like:    ETA:01.23'45"