Ban DoS fix

• Fix of ban DoS

v0.4.0 -> Active mode, local CMD handler, cool stuff

• Proper mitigation of slow loris base attack by implementing configurable amount of maximal allowed threads to be spawned (def. 50 a.k.a somewhere about 20 clients or 10 bots) (CVE-2020-8815)
• Anonymous private version usage statistics implemented (toggleable)
• Active mode implement
• Local command handler to edit config on-the-fly (see COMMANDS.md)
• Config option for disabling outputting to console
• Fix of metasploit exploit not working properly due to temp.limitations
• Fix of incorrect date in LIST (was broken in some clients)
• Removal of file dumping function (will be re-added back after some code cleanup)

v0.3.1 -> Small fixes

• Fixed AllowAnonymous handling (oops)
• One more attempt to fix encoding break on some characters (only affects console)
• Fixed improper handling of incoming data on base socket (a.k.a base socket thread overuse fix)

v0.3.0 -> Big configuration update!

• Toggleable anonymous logins
• Per-IP logs (create "iplogs" folder for it to work properly)
• Max connections per second and max active connections are now changeable
• Buffer size can now be changed (def.8192)
• Fixed lower-case command handling
• Final attempt to fix an encoding bug related to outputting control characters
• Changeable bantime
• Toggleable ban on big amount of errors (a.k.a some sort of service probe)
• Moved default config to Resources

Tested to work: Windows 10, Ubuntu 18.04

v0.2.1 -> Minor bug fixes. Ping fixes

• Bans fix
• Fixed clients requesting RETR and STOR right after PASV without actually connecting to it properly (a.k.a high ping PASV fix) (There are still troubles with big files (more than 1 MB))
• Minor fixes of improper command handling
• Increased block size for RETR from 2048 to 8192‬, potentially increasing the speed of download
• REST command handling (improper but still)
• Fix of CLNT command

v0.2.0 -> AntiSpam Beta update!

• Fixed "errors" handling, designed to prevent users spamming invalid FTP commands
• Fixed PWN not being logged due to its size
• Added "connections per second" and "total connections" antispam for default port
• Added "total connections" antispam for PASV port
• Fixed PASV mode handler not checking for default port connection, as well as fixed handling of non-active users (CVE-2020-8416 fix)
• Passive mode now autodisconnects AFK persons after 120 seconds of inactivity (Beware when sending big files!)
• Minor bugfixes

v0.1.0 -> Big files Beta update!

• Ability to RECV files more than 2 kbs in size
• Ability to add byte[] contents to files (a.k.a you can now send .exes over FTP)
• JSON format fixed
• Possible fix of unique characters breaking encoding of logs.
• Download speed limited to 40 kbit/sec.

v0.0.1 -> GitHub Beta!

We actually moved from hardcoded values to configurable stuff, and made BearFTP an opensource public project.