Witnesses say strong currents in the Milwaukee River capsized a kayak and a canoe and trapped three men on an island in Lime Kiln Park Sunday evening.  The men managed to swim to shore, but couldn’t get off the island without the help of the Grafton Fire Department.  Rescuers say it took eight firefighters several hours to bring the boaters to safety.  No injuries were reported.  Fire officials are asking people to stay off the Milwaukee Rivers until its water levels recede and the currents aren’t so dangerous.