Update unit tests to verify correctness of six-part cron expressions.
Update unit tests to verify correctness of six-part cron expressions.

micheltol/ncrontab,cyotek/ncrontab,youniss2013/ncrontab,dabutvin/ncrontab,amitapl/ncrontab,codesharpdev/ncrontab,xingh/ncrontab,vasiliy-vdovichenko/ncrontab,IntranetFactory/ncrontab,JophyJob/ncrontab,paulgmiller/ncrontab,jakesays/ncrontab,xingh/ncrontab,devnarayan/ncrontab,rog1039/ncrontab,paulgmiller/ncrontab,petlof/ncrontab,codeyu/ncrontab,IntranetFactory/ncrontab,bjorskog/ncrontab,joshberry/ncrontab,klunwebale/ncrontab,DanThiffault/ncrontab