To Princess Diana’s former butler, Buckingham Palace was the “gin palace,” where the drinks never stopped flowing. Paul Burrell, who served at the royal residence for 11 years before moving to Kensington Palace, has written a new book,  “The Royal Insider. ” In it, he said that gallons of gin were consumed every week, “some legitimately, some not.” “I quickly became familiar with the ingenious ways in which the household smuggled booze for their soirées,” he wrote, as quoted by  The Sun . “I