It always bugged me that the "Duplicating Data CDs" section had "This
doesn't work for audio CDs" at the end, with no explanation as to how to
duplicate audio CDs.

Since I needed to do this recently, document the process. Note that I
don't have an ATAPI CDRW drive, so the ATAPI examples are based on some
googling and IRC discussions.

While I'm here, remove some <option>s and <filenames> that had snuck
into some <userinput> elements.