added constructor

src/main/java/kieker/analysis/domain/systemdependency/SoftwareSystem.java

@@ -11,6 +11,8 @@ public class SoftwareSystem {
 	private Collection<Dependency<Component>> componentDependencies = new ArrayList<>();
 	private Collection<Dependency<Operation>> operationDependencies = new ArrayList<>();
 
+	public SoftwareSystem() {}
+
 	public Collection<Container> getContainers() {
 		return containers;
 	}