message: Documentation for ospCancel
diff: @@ -2810,7 +2810,11 @@ function
  float ospGetProgress(OSPFuture);
  -This returns the progress of the task in [0-1].
  +This returns the approximated progress of the task in [0-1].
  +
  +Applications can cancel a currently running asynchronous operation via
  +
  + void ospCancel(OSPFuture);
  Applications can wait on the result of an asynchronous operation, or
  choose to only synchronize with a specific event. To synchronize with an
  