The family of GOP presidential candidate Rick Perry owns a hunting camp in Texas known to many locals as “Niggerhead,” a name that appears on a large rock on the property. Perry claims his father painted over the name as soon as he bought the land, although some in the area dispute the governor’s timeline. Niggerhead was a fairly common place name in the 19th century. How many racially offensive place names are still around? Hundreds, at least. It’s impossible to say precisely how many offensively named towns and geographic features remain within the nation's borders. State lawmakers don't always...