FIX: reduce information disclosure in error messages.
CLEAN: lower trace level of "make run"
FIX: thread race when updating dir->sortField.
FIX: CGI hang when CGI process fails until request timeout.

Ensure response generated immediately
Also reduce information disclosure on error message.
FIX: dirHandler thread race on sortField.
FIX: CGI handling when exec() fails for CGI program.f