iCalendar on b.g.o now supports priority

Bugzilla didn’t want priority in the iCalendar as the priority fields are configurable. This would break iCalendar. At the request of William Jon McCann (who originally wrote the iCalendar for Bugzilla) I added the priority to bugzilla.gnome.org with as result:

The priority is shown by the color (all blue at the moment)