The log file is specified via [[logFile]]. If the size of the log file exceeds
[[maxFileSize]] (in kilo-bytes), a rotation will be performed, which renames
the current log file by suffixing the file name with '.1'. All existing log
files are moved backwards by one place, i.e., '.2' to '.3', '.1' to '.2', and so on.
The property [[maxLogFiles]] specifies how many history files to keep.