Reverses direction of a relationship. Switches relation source with target.
An example how to reverse a relationship:
// We have an arbitrary element which represents a relationship.
Element element = ...;
// Relationship reversing should be wrapped with session create/close calls.
SessionManager sessionManager = SessionManager.getInstance();
sessionManager.createSession("Reverse relation");
// Reverse the relationship.
Refactoring.RelationReversing.reverseRelationDirection(element);
// Close the session.
sessionManager.closeSession();