Initial support for bandwidth/traffic control/shaping.

• Implemented bandwidth rate control.
• Traffic shaping works on both directions: ingress/outgress.
• Introduced usage of ifb kernel module to redirect ingress and be able to filter it.
• Added iftop as new dependency.
• Added tc as new dependency needed for traffic shaping.

Working support for banning rules per port or port range

• Implemented banning rules per incoming port.
• Print remaining time on bans list.
• Renamed PORT_MAX_CONNECTIONS to PORT_CONNECTIONS
• Updated man page.
• Updated ddos.conf file.
• Restored bsd support by using netstat if ss is unavailable.
• Use ipfw to block ipv6 addresses on bsd.

Major bug fixes and overall improvements

• Fixed syntax error introduced in 1.0 thanks to @MarcelFox
• Fixed issue #36 (cron file created incorrectly).
• Added cron job deprecation warning, daemon mode should be used instead.
• Fixed many issues reported by shellcheck.
• Added IPv6 support
• Use ss instead of netstat.
• started some drafting to add blocking by port support.
• Improved ban_incoming_only
• Eliminate some command steps to improve performance.
• Removed HOST_IP since it is no longer necessary.
• Fixed improper call to grepcidr.
• Minor man page changes.
• Added ip6tables to dependencies list and removed netstat.

Added suppor for ip ranges, cidr and other improvements

• Support for ip ranges and cidr on the ignore.ip.list thanks to @safly (https://github.com/safly)
• grepcidr install requirement introduced with the support for CIDR
• New syntax supported on ignore.ip.list
  a.b.c.d/xy (CIDR format)
  a.b.c.d-e.f.g.h (IP range)
  For more details read the grepcidr man page.
• Fixed bug $CONF not found thanks to @WoozyMasta (https://github.com/WoozyMasta)
• Added unban flag -u --unban
• Added logrotate configuration file to uninstall script.
• Prioritize systemd detection on install script.

BSD support and other improvements

• Support for freebsd and many other improvements thanks to Marc S. Brook (https://github.com/nuxy)
• Added option to only block incoming connections thanks to Fathardie (https://github.com/Fathardie)
• Optional automatic installation of dependencies on the install script thanks to gloomy-ghost (https://github.com/gloomy-ghost)
• Some other fixes and improvements thanks to mean-cj (https://github.com/mean-cj)