a97e726622
The aim is to make php handlers not always required when there is a FTP server that supports "SITE MD5" commands (like proftpd with mod_md5). This commit makes FtpServerHandler able to handle such feature and avoid using any other external hook. If server support is found, this verification is enough. If support is broken, FtpServerHandler will try to fallback to previously supported features, if enabled (use_handlers variable). Moreover, FtpServerHandler now makes use of entropy.tools.is_valid_md5 instead of just checking if provided strings are long 32 chars.