More detailled error messages while starting and anding statecharts

See merge request !50

Fix ArmarXGui search field to create a widget if enter is pressed and the widget name is already entered

* 'master' of https://gitlab.com/ArmarX/ArmarXGui:
  Add EnhancedGraphicsView (a QGraphicsView with zoom, rotation and translation via keyboard and mouse)
  Fix error in ObserverItemModel::getPropertiesWidget
  Remove compiler warnings

Add EnhancedGraphicsView (a QGraphicsView with zoom, rotation and translation via keyboard and mouse)

Make WidgetDescription::Widget a framed widget and add a parameter whether the frame should be shown

Replace LabeledWidget with FormLayoutElement (now the label can be a widget/the element can be spanning)

Change the base of gui plugins from ArmarXComponentWidgetController to the CRTP version ArmarXComponentWidgetControllerTemplate

Add a CRTP base ArmarXComponentWidgetControllerTemplate for ArmarXComponentWidgetController (it uses the static get name/icon functions to override the virtual versions)