Who knew a movie with such a ridiculous title could actually be a bubbling Jacuzzi of crazy fun, but that’s exactly what Hot Tub Time Machine is. Somewhat aimed at GenX-ers, Hot Tub is one screwball situation after another. It’s absurd and raucous, but unlike the majority of crap today masquerading as comedy behind cheap gross-out and sex gags, Hot Tub manages to be tasteful and witty even while employing that same pantheon of jokes…