pH-window: Creating the menubar in a different method
pH-central_widget: Created the c_central_widget class
pH-central_widget: Added the f_init method
pH-central_widget: Creating the c_tab_displayer inside the c_central_widget
pH-central_widget: Added c_central_widget* to the CMakeList
pH-tab-display: c_tab_displayer now is contained by c_central_widget
pH-window: the window now handles a c_central_widget
pH-central_widget: The central_widget is now operational
pH-window: Removed a useless delete
pH-error display: Created the c_error_displayer class
pH-central_widget: Created a vertical layout
pH-central_widget: Created the c_error_displayer instance
pH-error display: Added the error_displayer in the central_widget
pH-license: License description of the c_central_tab class
pH-license: License description of the c_error_displayer class
pH-filter: Created the c_filter_displayer class
pH-filter: Created the c_filter_displayer instance