Coincident intersections

Fix for #1605.

I'm seeing two test failures, which show up on both this branch and master, so it may be a machine configuration issue; perhaps someone else can confirm.

    Tests in error: 
      test2f1(org.opentripplanner.mmri.OnTripTest)
      testPlannerstackScenario(org.opentripplanner.mmri.PlannerstackScenarioTest)