static JPanel northCenterAndSouthWithMargin(Component n, Component c, Component s) {
  ret northCenterAndSouth(withBottomMargin(n), c, withTopMargin(s));
}

static JPanel northCenterAndSouthWithMargin(int margin, Component n, Component c, Component s) {
  ret northCenterAndSouth(withBottomMargin(margin, n), c, withTopMargin(margin, s));
}