It snowed Friday, horrid stuff, and it's a bit chilly today but tomorrow is the first day of spring. And I know it's on its way because Wednesday I saw my first sign: neighbor Al outside with his wheelbarrow, working away. Forget crocuses and robins. There he was, my very own harbinger, across the street in his bright yellow hat (a hard plastic thing he's had since he lived in Quincy, he once explained), light aqua jacket with a little pink trim, (very colorful), blue jeans and sneakers and work gloves, rake in one hand, shovel in the other, scooping up a winter's worth of dead leaves…