Modify calculation of h_rfptime array to match HCANA
h_rfptime is now the average focal plane time of paddles with
  two_good_times=.true. for each plane.
Previously it was the focal plane time for each plane but if multiple
  paddles in a plane had two_good_times=.true. then h_rfptime was filled
  with fp time of last paddle hit for that plane.
Did not effect the start_time calculation.