It doesn't do much good to link to a png file unless you actually create
the png file.
(This includes the patch to make lilypond-book stop ignoring -f)
--- /usr/bin/lilypond-book 2005-03-10 19:08:41.0 -0700
+++ lilypond-book 2005-03-19 20:07:29.329192264 -0700
@@ -1444,11 +1
lilypond-book (2.5.15) ignores the --format option.
--- /usr/bin/lilypond-book 2005-03-10 19:08:41.0 -0700
+++ lilypond-book 2005-03-19 18:35:54.586520120 -0700
@@ -1444,7 +1444,8 @@
file = files[0]
global process_cmd, format
- format = guess_format (fil
