[Forseti] Hangs on generating seating

[Jesterboxboy]

When using predefined seating for a tournament event, and more players are added than are accounted for in the predefined seating, I.e. the seating only has numbers 1-20, but 24 players are added to the event(local ids 1-24), then starting "Next seating" results in the process hanging without the possibility to finish it via the webgui.
A db_import from a db backup solved the problem.
There should be a precheck and a warning if the number of players added to the tournament is not equal the number of players in the predefined seating.