python security, bug fix, and enhancement update

python: 2.6.6-20 Resolves: CVE-2010-3493 2.6.6-19 Resolves: CVE-2011-1015 2.6.6-18 Resolves: CVE-2011-1521 2.6.6-17 - recompile against systemtap 1.4 Related: rhbz569695 2.6.6-16 - recompile against systemtap 1.4 Related: rhbz569695 2.6.6-15 - fix race condition that sometimes breaks the build wi...