By Andrew MacAskill, Kylie MacLellan and Sachin Ravikumar LONDON, May 26 (Reuters) - More than 13,000 people were denied a vote in English local elections this month because of the government's new identification law, with those in poorer areas most impacted, according to a Reuters survey of local authorities. Voters in England were legally required to produce photo ID for the first time at the May 4 elections, with the government saying it was essential to combat election fraud. But the overhau...