This patch adds an "inline" option, which removes the <p> and <a> tags
from around the music image.

This came from the desire to include small music images within a line of
text, rather than in a separate paragraph.

It can also be used if you wish you do your own <a> tag, for example,
to link to a midi file instead of the ly file.  Or if you do not want
the image to be a link at all.