The command by which your favourite browser is invoked.  It is used by
pfm to display the on-line help.

Use '%s' as a placeholder for the URL.

Use curly braces { and } to delimit filenames containing spaces.

Examples:

    - UNIX: mozilla -remote "openurl(%s)"
            konqueror %s

    - Windows: {C:/Program Files/Internet Explorer/iexplore.exe} %s
               {C:/Program Files/mozilla.org/Mozilla/mozilla.exe} %s

      Note: Use '/' instead of '\' as directory name separator.
