Include tests that can create cycles in the graph

[sabbyanandan]

Include tests that can create cycles in the graph

[cppwfs]

While the UI gives the user the ability move the arrows to create a cycle, the DSL that is generated is incorrect as shown here:
When the user attempts to create the Composed Task the server will throw an exception and the UI will report an error back to the user. This is a UI issue where a user should not be allowed to move the exit arrow to a previous stage in the graph. i.e. where DDD refers back to AAA