Added gui functionality for TransitionFunctions

...-plugins/StatechartEditorPlugin/StateEditorController.cpp

...ui-plugins/StatechartEditorPlugin/StateEditorController.h

...rXGui/gui-plugins/StatechartEditorPlugin/io/XmlReader.cpp

...rXGui/gui-plugins/StatechartEditorPlugin/io/XmlWriter.cpp

...marXGui/gui-plugins/StatechartEditorPlugin/io/XmlWriter.h

...i-plugins/StatechartEditorPlugin/model/StateTreeModel.cpp

...arXGui/gui-plugins/StatechartViewerPlugin/model/State.cpp

...rmarXGui/gui-plugins/StatechartViewerPlugin/model/State.h

...Gui/gui-plugins/StatechartViewerPlugin/model/Transition.h

...Gui/gui-plugins/StatechartViewerPlugin/view/StateItem.cpp

...ui-plugins/StatechartViewerPlugin/view/TransitionItem.cpp

.../gui-plugins/StatechartViewerPlugin/view/TransitionItem.h