code: public List<ISubmission> include(List<ISubmission> submissions, List<String> submitters){
  		ArrayList<ISubmission> filteredSubmissions = new ArrayList<ISubmission>();
  		for (ISubmission submission: submissions){
  			if (submission.getSubmitter() != null){
  				if (submitters.contains(submission.getSubmitter().getSubmitter()))
  					filteredSubmissions.add(submission);
  			}
  		}
  		return filteredSubmissions;
  	}
docs: Filter a set of submissions including only submissions from submitters whose
  names are in the include list
  @param submissions the submissions to filter
  @param submitters the submitters to include
  @return the filtered list of submissions