Provide better icon files

[Scott Wegner]

Per the packaging guidelines:

Some ideas about icons:

    * Provide an 32x32 pixel XPM icon for use by the Debian menus
    * Optionally provide a 48x48 pixel PNG icon for use by freedesktop.org menus (the Debian icon will be used if this is unavailable)
    * If neither format is available, many formats can be converted as follows:
         1. Get a base icon (clip of package graphic, .ico file, from scratch, etc.)
         2. Crop / resize to 32x32 pixels
         3.

            run convert editedicon.ico <package>.xpm (requires imagemagick)
         4. if convert generated multiple images, select one (and name correctly)