Enforce rename

[moaxcp]

Vertex has the property name. This should not be set directly outside of the package. Instead rename should be used within the dsl.

• make setName package private in Vertex.

Edge has the properties one and two. These should not be set directly outside of the package. Instead renameOne and renameTwo should be used in the dsl.

• make one and two package private in Edge.

[moaxcp]

Will need to add tests outside of package to test this works.

[moaxcp]

Because of GROOVY-3010 testing cannot be done. It is unfortunate that groovy has not fixed this yet.