Mark as broken: fails to configure:
===> Running extconf.rb to configure
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers. Check the mkmf.log file for more
details. You may need configuration options.
Provided configuration options:
extconf.rb:24:in ``': No such file or directory - audiofile-config --libs
from extconf.rb:24:in `<main>'
*** [ruby-extconf-configure] Error code 1