TODO

* Reimplement configuration reloading
* PID file
* Improved table backend lookup, currently this is a linear search
** Considering breaking hostname appart at label bounderies and search backwards from TLD
* Move from select() to libevent to support more than FD_SETSIZE / 2 connections
* Non-blocking DNS resolution
* Improve handling of unparsable TLS client hello messages
** Optionally dump client hello to file
** Optionally use a fallback hostname/backend server
* Refactor logging so unit tests do not log to syslog
* HTTP or DNS interface for backend servers to determine remote IP and port of connection
* Per connection access logging including hostname, bytes rx/tx, src/dst ip/port, timestamp and duration