This week the Globe introduces a new advice column to this page. “Ask Amy” is written by Amy Dickinson, who succeeded the legendary Ann Landers as the Chicago Tribune’s reader advice columnist. To make room for “Ask Amy,’’ we have to say goodbye to a few columns, including our Poker column, “Annie’s Mailbox,” and “Surfing the Net With Kids.” These changes bring Globe readers a feature that has been highly popular in newspapers around the country.