MOSCOW, April 22 (Reuters) - The veteran leader of Russia's Communist Party has warned parliament that the country's faltering economy risks stoking a 1917-style revolution and that the government needs to take urgent measures to correct its course. Gennady Zyuganov, 81, issued his warning to a plenary session of the State Duma, the lower house of parliament, ahead of a parliamentary election due in September, according to a recording of his speech posted on the Duma's official website. "We’re doing everything we can to support (President Vladimir) Putin and his strategy and policies, but you (the government) are not listening,"...