Rainbows! 1.0.0 - internal cleanups

This release is merely a milestone in our evolving internal API.
Use of kgio may result in performance improvements under Ruby
1.9.2 with non-blocking I/O-intensive workloads.

The only bugfix is that SIGHUP reloads restores defaults on
unset settings.  A similar fix is included in Unicorn 2.0.0
as well.