Trade Route Confirmation

At present the NPC Pilots only seem to check that the start and destination points of their routes exist before accepting the route.

For months now I have had some of my NPC Pilots effectively doing nothing. I have not bothered with them, but as I had a bit of time on my hands I thought I would find out if there was a reason they were moving nothing or if it was just the usual laziness on their part.

I eventually tracked down that there was a reason: there was not a Jump Gate route between the two colonies.

I had not thought to check this before, because I assumed, wrongly as it happens, that before accepting the route, the AI would actually check that there was a route to follow.

I think this may be the cause why we have so much trouble with NPCs. I think that it would be an excellent idea for the AI to check that the NPC can actually fly the route ordered before accepting the route.