test condition in test_proj_data_info_subsets.cxx is wrong

[KrisThielemans]

STIR/src/test/test_proj_data_info_subsets.cxx

Lines 483 to 488 in 209db3c

	if ((template_sino_sptr->get_min_segment_num() > 0) && (template_sino_sptr->get_max_segment_num() < 1))
	{
	cerr << "Error: Template provided doesn't have enough segments to conduct this test with "
	<< template_sino_sptr->get_num_segments() << " segments." << std::endl;
	everything_ok = false;
	}

This should be template_sino_sptr->get_min_segment_num() > -1).
Also, I don't think this test should fail if the input data doesn't have enough segments, it should just return.