Backport of libyaml-0.1.4 from precise to Lucid

So that we can include http://www.ubuntu.com/usn/usn-2098-1/

No fix for Lucid has been released because it's been deemed to be end-of-life (http://people.canonical.com/~ubuntu-security/cve/2013/CVE-2013-6393.html), even though https://wiki.ubuntu.com/LTS would suggest it should be supported into 2015.