some fixes inside extensions

* do not use private variables if there are special methods
* change macro call from `aw_*` to `aw_macro_*`
* add forgotten configuration reading/writting for list formatter

sources/awesomewidgets/awlistformatter.h

@@ -48,7 +48,9 @@ public:
     void setSorted(const bool _sorted);
 
 public slots:
+    void readConfiguration();
     int showConfiguration(const QVariant args = QVariant());
+    void writeConfiguration() const;
 
 private:
     Ui::AWListFormatter *ui = nullptr;