Add GO IDs to go2obj that are involved in relationships.

def fill_relationshipobjs(go2obj, relationships):
    """Add GO IDs to go2obj that are involved in relationships."""
    # Get all GO Term record objects that have relationships
    obj = RelationshipFill(go2obj, relationships)
    for goobj in go2obj.values():
        if goobj.relationship:
            obj.fill_relationshipgo2obj(goobj)
        if goobj.relationship_rev:
            obj.fill_relationshiprevgo2obj(goobj)