COSTA MESA, Calif. - The mantra is money is tight, so is time. Even with the siren call of summer, many vacationers this year are looking to keep things a little shorter, a little less expensive. Even a whole hog trip to San Diego might be a bit too much this year. So we're offering up slices of San Diego - little morsels that can be collected together and perhaps turned into a one- or two-day t…