Fix sittings spidering on an empty DB
Fix sittings spidering on an empty DB

Attempts to resume spidering from the last voting would fail when the
database didn't have any votings in it.

Fixes #72.

ManoSeimas/manoseimas.lt,ManoSeimas/manoseimas.lt,ManoSeimas/manoseimas.lt,ManoSeimas/manoseimas.lt