allow two divisions to have the same name if they have different colors and both are ignored, that way we can have a Frontier with 0,0,0 that gets erased while in the Place division in its position and the Frontier with != 0,0,0 that is not erased in that mode and there's no need for things like Frontier and External Frontier that are a bit forced imho

svn path=/trunk/KDE/kdeedu/kgeography/; revision=604343