errorlog is preferred but it is a bug to by default set it to empty string
errorlog is preferred but it is a bug to by default set it to empty string

- errorlog set to empty string by default
- since it is the preferred value this causes an error
- instead set errorlog to a value ‘server.log’ and comment out logfile by default

NYUCCL/psiTurk,NYUCCL/psiTurk,NYUCCL/psiTurk