update readme with new char-rnn timing
update readme with new char-rnn timing

hughperkins/clnn,szagoruyko/clnn,hughperkins/clnn,szagoruyko/clnn,brunoro/clnn,szagoruyko/clnn,hughperkins/clnn,brunoro/clnn,szagoruyko/clnn,brunoro/clnn,brunoro/clnn,hughperkins/clnn