The enclosed patch makes indian settlements visible in the game
world. It activates the IndianSettlement generation in
MapGenerator, adds appropriate support to Tile and other such
classes, and gives the Client the capability to display the
IndianSettlement tiles when they're encountered.
You'll need to add the indian graphics; I just snagged the Aztec
city image from freeciv for testing.
Also note that there is some complication in that the IndianSettlement
images are not numbered from 0 as they should but instead from
1+numColonies, which messes things up; I set index=0, but more
work in this area is needed.