addAdjacency id fix

When using the @Adjancency annotation with an addNewThing() method you
get a new object with the object's class as its id in the graph.  I
changed the id to null so the underlying graph would set the id instead.

I also added a test that adds two vertexes using addKnowsNewPerson.
This would have failed without the above fix, because it would try two
add two Person vertexes with the same id (Person.class).
refactored FramedVertexTest for brevity

Using set comparison makes the test shorter and easier to read.
Merge branch 'dsiegel-2.4.1'

Conflicts:
	CHANGELOG.textile
	pom.xml