StarGraph does not handle self-loops correctly.

gremlin> graph = TinkerGraph.open()
==>tinkergraph[vertices:0 edges:0]
gremlin> v = graph.addVertex()
==>v[0]
gremlin> v.addEdge("self",v)
==>e[1][0-self->0]
gremlin>
gremlin> g = graph.traversal()
==>graphtraversalsource[tinkergraph[vertices:1 edges:1], standard]
gremlin> g.V(0)
gremlin> g.V(0l)
==>v[0]
gremlin> g.V(0l).bothE()
==>e[1][0-self->0]
==>e[1][0-self->0]
gremlin> g.V(0l).outE()
==>e[1][0-self->0]
gremlin> g.V(0l).inE()
==>e[1][0-self->0]
gremlin>

/////////

gremlin> starGraph = org.apache.tinkerpop.gremlin.structure.util.star.StarGraph.of(v)
==>stargraph[starOf:v[0]]
gremlin> sg = starGraph.traversal()
==>graphtraversalsource[stargraph[starOf:v[0]], standard]
gremlin> sg.V(0l)
==>v[0]
gremlin> sg.V(0l).bothE()
==>e[1][0-self->0]
gremlin> sg.V(0l).outE()
gremlin> sg.V(0l).inE()
==>e[1][0-self->0]
gremlin>