FileTimesExtractor.scala: Made method "determineTimePeriod" more "functional-style" and changed method names "findNextTimeStamp" -> "nextTimeStamp" and "findLastTimeStamp" -> "lastTimeStampAfter". LogFile_WithNameTimeStamp_YYMMDD_hhmm_WithLineTimeStamp_YYMMDD_hhmmssms.scala: Deleted obsolete main method.