code: public Relation newRelation(Relational from, Relational to) {
  	String newId = idManager.getNextId(AnnotationType.RELATION);
  	Relation newRelation = new Relation(newId, from, to);
  	annotationContainer.add(newRelation, Layer.RELATIONS, AnnotationType.RELATION);
  	return newRelation;
      }
docs: Creates a new relation between entities and/or sentiment features. It assigns an appropriate ID to it. The relation is added to the document.
  @param from source of the relation
  @param to target of the relation
  @return a new relation