Taskbar plugin was created using code from the Window Buttons plugin, written by Nick Schermer

1) Make sure you've got the development packages
    
    # Valid for XUbuntu 12.04
    make devenv

2) Build and install the plugin:

    make
    sudo make install
    xfce4-panel -r # restart the panel
    # It should now be in 'Add New Items' option via panel context menu

3) To remove the plugin

    sudo make uninstall

4) For development

    #uninstall, install, restart the panel
    make restart

** Usage Notes **

    <Super> + number will activate the pinned application indexed by the
    number (Super is the so-called 'Windows' key)
    
    Right-click on an application icon will give you the option to pin/unpin
    the app
    
    Left-click on the application icon has context dependent behaviour:
    
        1) If it is a pinned icon and there are no application instances
        running, the associated application is started
        
        2) If there is a single application instance running, it is raised
        or lowered, depending on it's current state
        
        3) If there are multiple application instances running, a list to
        the application windows is shown

** Known Issues ***
    
    Drag and drop of applications from the applications menu or the desktop
    does not work (yet)
    
    The windows are grouped by wnck class resource name
    This appears to be a somewhat volatile property as some applications 
    use different class names depending on the context in which 
    they're executed (for example, Google Chrome)
    
    The pid of the process is extracted via the Wnck API. This is used
    to track down the command line via the proc/$pid/cmdline entry. Unfortunately
    the command used to start the application may not be the same as the binary used to
    drive the application, for example, Thunderbird is started via a script in /usr/bin
    but it actually driven by an executable under the lib directory,
    /usr/lib/thunderbird-7.0.1/thunderbird-bin, the shell script is used to setup libpaths, 
    without which the application cannot run

** Additional Configuration **

    ~/.config/xfce4/panel/taskbar/taskbar.rc

    The taskbar.rc file holds information about pinned applications. This file
    can be edited to modify the launch command of any pinned application. To apply
    new settings, save the file, then restart the xfce panel with the terminal command:

    xfce4-panel -r
