Fix bug: first card generation assumes qlines is 1

Noticed this while using poem2anki to generate a deck for another wedding reading.

I like to have a couple of lines 'lead up' as a prompt.  The existing code would generate a first card that had `n-1` blank lines, if I set `qlines` to `n`.

If you see what I mean.

This is one of those situations where code is more succinct than English.  Hope it makes sense!