It seems that a pink elephant, a green monkey and a purple snake walked into a bar. . . ""You guys are a little early tonight,"" says the bartender, ""He ain't here yet."" Now you know, as you yawn through all that introductory advice on making speeches, that Georgie ain't here yet. And well into the alphabetically listed jokes (averaging one strangler per 25 pages) that the Orator has probably never electrified this deadwood with his sonic boom. However, if you're desperate for one to knock 'em dead at the Y, how about the cannibal in the ship's restaurant who is asked if he wants a menu: ""No,"" says the chief, ""just bring me the passenger list."" Now you take Henny Youngman. . .