[Freeciv-Dev] (PR#6155) Assert in traderoutehandling

["Jason Short" <jdorje@xxxxxxxxxxxxxxxxxxxxx>]

<URL: http://rt.freeciv.org/Ticket/Display.html?id=6155 >

Summary: if you establish a trade route in an enemy city 2 tiles away
from your homecity, then conquer that city, you'll have a trade route
going just 2 tiles.  This triggers an assert.

Possible solutions:

- Remove the assert and allow short traderoutes (although they still
can't be created).

- Remove the traderoute when conquering the city.

- Don't allow traderoutes even to enemy cities if they are too close.

jason