[BUG] Doesn't allow LW in day of month, or mixed case for months and days.

[grumBit]

After reading through the Quartz Job Scheduler Cron Trigger Tutorial and trying things out on the AWS EventBridge console, I found these two things were not being allowed;

• The L and W characters can also be combined in the day-of-month field to yield LW, which translates to "last weekday of the month"
• The legal characters and the names of months and days of the week are not case sensitive. MON is the same as mOn.