Ajout graphedge

modeling/AVATAR/testDependencyGraphs.xml

src/main/java/avatartranslator/AvatarDependencyGraph.java

src/main/java/ui/TGUIAction.java

src/main/java/ui/graphd/GraphDPanel.java

src/main/java/ui/tree/DiagramTreeRenderer.java

src/main/java/ui/util/IconManager.java

src/main/resources/ui/util/graphaut.gif

src/main/resources/ui/util/graphedge.gif