LONDON, ENGLAND - NOVEMBER 23: Former 'Doctors' form the classic series 'Doctor Who' (L-R) Tom Baker (1974-1981), Peter Davison (1981-1984), Colin Baker (1984-1986), Sylvester McCoy (1987-1989, 1996) and current Doctor Matt Smith (2010-present) pose at the 'Doctor Who 50th Celebration' event in the ExCeL centre on…