THREE AND A HALF STARS John Davidson has Tourette's. Everyone thinks he's inappropriate and swears too much. DRAMA UK English #ISWEAR Starring Robert Aramayo, Maxine Peake Kirk Jones (WAKING NED DEVINE ) is no stranger to sentiment, and I SWEAR is no exception. Based on the true story of John Davidson, a Scotsman diagnosed as a teenager with Tourette syndrome, it’s a film with heart, humour and a fair amount of grit. If it doesn’t quite stick the landing, it certainly at lea