bugfixes for PrepareFullAnnotationJson, RoteSegmenter

PrepareFullAnnotationJson was combining frames that had the same name.
RoteSegmenter was choking on postags with less than two chars.
Added regression tests for both bugs.
Exposed more methods in Semafor.
Merge branch 'master' into targetid

Conflicts:
	src/main/java/edu/cmu/cs/lti/ark/fn/evaluation/PrepareFullAnnotationJson.java