Refactorings to avoid memory leaks.

plugins/org.yakindu.sct.ui.editor/src/org/yakindu/sct/ui/editor/breadcrumb/BreadcrumbDiagramEditor.java

@@ -180,5 +180,10 @@ public abstract class BreadcrumbDiagramEditor extends DiagramDocumentEditor {
 		}
 
 	}
-
+	
+	@Override
+	public void dispose() {
+		history.clear();
+		super.dispose();
+	}
 }

plugins/org.yakindu.sct.ui.editor/src/org/yakindu/sct/ui/editor/wizards/CreationWizard.java

@@ -156,12 +156,12 @@ public class CreationWizard extends Wizard implements INewWizard {
 
 		};
 		try {
-			OperationHistoryFactory.getOperationHistory().execute(command,
-					new SubProgressMonitor(progressMonitor, 1), null);
+			command.execute(progressMonitor,null);
 		} catch (ExecutionException e) {
 			e.printStackTrace();
 		}
 		setCharset(WorkspaceSynchronizer.getFile(resource));
+		editingDomain.dispose();
 		return resource;
 	}