rendering: avoid drawing twice

[dnaber]

In MapPaintVisitor.visit(), do we really need this line?:

Draw segments in a different colour so direction arrows show against the fill
drawSeg(lastN, n, w.selected ? selectedColor : untaggedColor, showDirection, width, true);

A few lines below, almost exactly the same method is called again (using dashed instead of true as the last parameter, and a different color in case of !w.selected), sometimes drawing the same line again. I tried to comment out the first drawSeg call and it does indeed make rendering quite a bit faster. I didn't see what use case is broken by removing that statement.

[anonymous]

Fixed in r757.