Changed the toolbox node icons

- replaced all pngs of nodes with my own

scopviz/src/main/java/de/tu_darmstadt/informatik/tk/scopviz/ui/ToolboxManager.java

@@ -66,7 +66,7 @@ public final class ToolboxManager {
 
 		@SuppressWarnings("unchecked")
 		ObservableList<Pair<Object, String>> data = FXCollections.observableArrayList(
-				pair(new Image(MainApp.class.getResource("/png/standard.png").toString()), "Standard"),
+				pair(new Image(MainApp.class.getResource("/png/standard_operator.png").toString()), "Standard"),
 				pair(new Image(MainApp.class.getResource("/png/procEn.png").toString()), "ProcEn"),
 				pair(new Image(MainApp.class.getResource("/png/source.png").toString()), "Source"),
 				pair(new Image(MainApp.class.getResource("/png/sink.png").toString()), "Sink"),
@@ -82,7 +82,7 @@ public final class ToolboxManager {
 
 		@SuppressWarnings("unchecked")
 		ObservableList<Pair<Object, String>> data = FXCollections.observableArrayList(
-				pair(new Image(MainApp.class.getResource("/png/operator.png").toString()), "Operator"),
+				pair(new Image(MainApp.class.getResource("/png/standard_operator.png").toString()), "Operator"),
 				pair(new Image(MainApp.class.getResource("/png/source.png").toString()), "Source"),
 				pair(new Image(MainApp.class.getResource("/png/sink.png").toString()), "Sink"),
 				pair(new Image(MainApp.class.getResource("/png/dirEdge.png").toString()), "Directed"));
@@ -98,7 +98,7 @@ public final class ToolboxManager {
 
 		@SuppressWarnings("unchecked")
 		ObservableList<Pair<Object, String>> data = FXCollections.observableArrayList(
-				pair(new Image(MainApp.class.getResource("/png/dirEdge.png").toString()), "Directed"));
+				pair(new Image(MainApp.class.getResource("/png/dirEdge.png").toString()), "Mapping Edge"));
 
 		controller.toolbox.getItems().setAll(data);