Pity London's poor crafty underagers. A further hurdle was today placed in the way of their illegally buying booze and fags as supermarket chain Budgens unveiled a trial of hi-tech face-recognition cameras in one of its London stores – technology that will weed out teenage drinkers and smokers before they reach the tills. First the smoking ban. Then Boris's quaint 'don't drink on the tube' posters. Indulging in our favourite national pastimes is getting......