merge nginx changes between 1.2.5 and 1.2.6
change cpu affinity to 'off' as default
update cpu affinity log, so that nginx will write down 'cpuset_setaffinity' rather than 'sched_setaffinity' in freebsd
Merge pull request #177 from cfsego/merge

Merge changes between 1.2.5 and 1.2.6