The White Van by Patrick Hoffman Atlantic Monthly Press/Grove Atlantic, Inc., $24.00, 240 pages, ISBN 978-0-8021-2304-6 We’ve all been guilty, at some time or another, of staying at the party just a wee bit too long, or succumbing to the exhortations of one of our Good Time Charlie pals, to Awwwgoahead, one more won’t killya . . . and awakened the next day feeling like hammered doggie doo-doo. But