refs #312, some minor adjustments:

* cpp check (Jenkins)
* init style sheet in navigator
* shorter names in JSON plugin names

src/blackgui/components/navigatordockwidget.cpp

@@ -30,6 +30,7 @@ namespace BlackGui
         {
             this->allowStatusBar(false);
             ui->setupUi(this);
+            this->ps_onStyleSheetsChanged();
         }
 
         CNavigatorDockWidget::~CNavigatorDockWidget()

src/blackgui/guiutility.cpp

@@ -89,10 +89,10 @@ namespace BlackGui
         // http://stackoverflow.com/a/7569928/356726
         if (!layout) { return; }
         QLayoutItem *item {nullptr};
-        QLayout *sublayout {nullptr};
-        QWidget *widget {nullptr};
         while ((item = layout->takeAt(0)))
         {
+            QLayout *sublayout {nullptr};
+            QWidget *widget {nullptr};
             if ((sublayout = item->layout()))
             {
                 deleteLayout(sublayout, deleteWidgets);