Building new factory reduces Nano Tube production when not enough electricity is available

[daniel-sch]

When a new Factory is built without enough electricity to power it, the Alloy production will increase by 1, while the Nano Tube production goes down by 1. The expected outcome is that nothing changes, because the new factory is not enabled.

[yarukishi]

Fixed as part of PR #1010 (which also includes a new feature). The check to decide whether enough power is available for a new struct erroneously returns true when it should return false. This causes a powered-off new factory to increment alloy manufacturing. Then, the game loop disables factories from bottom to top until excess production is eliminated.