Cheat when reassigning signals

[Vladki]

I found that using the signal reassignment tool you can assign a signal that is out of signalbox coverage. Live examples in Simutrans Siemens game at (566,270) ad (644,1). It seems that the coverage of signalbox is not checked during reassignment.

[jamespetts]

Thank you for the report; I believe that I have now fixed this. I should be grateful if you could re-test and confirm with the next nightly build.