Too many recurrences "hang" `task`

I just started up `task` in a context where I had a very old task database. It "hung", and some investigation showed it adding tasks for a recurrence. Presumably most of those tasks had due dates in the past, and certainly all of them are not useful.

Perhaps we should either have a limit on the number of recurring tasks to create in a given report run, or just never create recurring tasks in the past.