Somewhat working out-edges retriever; it losts tags
Merge branch 'experiment/scala/model' of https://github.com/bio4j/bio4j into experiment/scala/model

Conflicts:
	scala-model/src/main/scala/bio4j/model/Edge.scala
	scala-model/src/main/scala/bio4j/model/EdgeType.scala
	scala-model/src/main/scala/bio4j/model/Vertex.scala
	scala-model/src/test/scala/bio4j/model/titan/TVertex.scala