HUMOR tends to be excessive, at times senseless. Take the joke about leaders from four countries aboard an airplane, bragging about their respective national wealth. The man from Saudi Arabia says he can pour barrels of oil off the airplane; the American claims to be able to spread tons of wheat, while the Frenchman says he can pour out gallons of perfume. The Indonesian, not to be outdone, kicks his maid off the airplane. "We have millions of dom