Browser
    
      Version 0
    
    This version shows how to implement in Java a very simple web
    navigatore, which only manage HTML pages. It is composed by a unique
    class Browser and
    uses a extra file Failure.html
    (this file is placed inside the project, but outside the source
    folder).
    
      Version 1
    
    
    Version 2
    
      - In this version, classes History
        and HistoryBar
        are unchanged.
- The class Browser
        has been renamed BrowserFrame.
        The frame is completed by adding a menu "File" which allow to
        create or close windows, or to quit the application. Note that
        the display of the frame (pack and show) is let to the client.
- The frames are managed by an instance of FrameController,
        implemented here by the class Browser. Note the
        use of a dialog to confirm or not for quitting the application.