[IMP]planner: Create a PlannerManager class, which contains init, start, fetch_application and on_menu_clicked.
When this object is instanciate, it will load all the planners, and store them.
The on_menu_clicked function will take the menu id as argument, and will find in the list of planner which on to display. A PlannerLauncher will be created and display.
In web.Menu, override on_top_menu_click, and trigger an event, and the id of the menu.
Override the Webclient class. In the start method, create an instance of PlannerManager. override show_application method inside that bind on_top_menu_click method of Menu.