Parser fails, if 7 is used as Sunday in day of week

[kipe]

Parsing 7 as DOW is non-standard, but worth considering, as it's a fairly easy mistake to make (I know, I did it).

Allowing 7 as Sunday allows also for such ranges as 6-7 for weekends, which is logical when using 1-5 for weekdays (this is where I made the mistake...).