On the night of Mr. Melvyn's murder, Sir Jasper Ippenstitch was cursing his jewish friend Eckmann for not warning him about betting on the fight.     He had lost it all, of course, when that no-good Don King had dealt him a double-fake and paid off Mike Tyson's opponent to take a dive in the second round. Even though the same Don King had sworn to him personally before the match that the fight had been fixed against Tyson.