Terminate loop when canceling waiting for wifi.
Implement ABOR, HELP, and STAT.
- STAT (no argument) during a transfer gives the current file's offset.
- STAT (no argument) outside of transfer will return server uptime.
- STAT (with argument) is the same as LIST but with the data traveling over the command socket.
Allow ABOR, STAT, and QUIT to occur during transfer.
Support telnet interrupt (discard data up to Data Mark past TCP urgent mark).
Support arguments for LIST and STAT.
Escape \r in response as per telnet standard. Some clients don't like this but they are out of spec.
Unescape \r\0 in request as per telnet standard. Some clients don't properly escape this but they are out of spec.
Support commands broken across multiple recv().
Escape quotes on PWD response.
Added much more documentation.
