[CTAKES-450] CDA Segment Annotator misses all headings after empty segment

[Alexandru Zbarcea <al...@apache.org>]

Hi,

I have provided another patch for CTAKES-450[1].

The fix provided in the original patch is correct. However, I tried to
address also small issues and some refactoring, especially addressing the
Unit Testing. If you think it requires more explanation, let me know.

* extracted methods
* removed dead code: sorted_segments.get(index + 1).getBegin();
* replaced deprecated junit.framework.Assert with org.junit.Assert
* assert for all elements in the jCAS, so in the future, if Segments aren't
processed well to be automatically identified
* replaced System.out.println with logger.

I think, this commit can fix and close CTAKES-450.

This diff is on top of latest trunk. As such, patching should be
straightforward.

I look forward to your feedback,
Alex Zbarcea

[1] - https://issues.apache.org/jira/browse/CTAKES-450