Print iOS font names in Swift 2

UIFont+FontNames.swift

extension UIFont {
    static func printFontNames() {
        for familyName in UIFont.familyNames() {
            print("Family name: \(familyName)")
            for fontName in UIFont.fontNamesForFamilyName(familyName) {
                print("Font name: \(fontName)")
            }
        }
    }
}