By Marilyn Lester****"Laughter the Best Medicine." The Reader's Digest ran this column for years. And it's true, particularly through the lens of lyricist Michael Colby's new "I've Been to a Virtual Party," a take on the Noël Coward standard, "I Went to a Marvelous Party." Humor, according to Psychology Today, is "…both a source of entertainment and a means of coping with difficult or awkward situations and s…