Start replacing select.select() for select.poll()
Move poll() logic to it's own class, and adapt Supervisor to use it.

Also fixing the poll() usage, my previous commit was registering all
file descriptors to all events, now register just on the expected events.
Remove select() method from Options class used by Supervisor
Ignores and unregisters closed file descriptors on poll()
Adjust log message to be more explicit
Handle POLLHUP on poll()
Add kqueue() support for poller
Add select() support for poller when no poll() or kqueue() is available. Make all tests pass for py>=2.5
Handle EBADF on kqueue poller backend
Use set instead of list for readables and writables on SelectPoller
Restore kqueue after daemonize because it's not inherited on fork()
Remove file descriptor from sets on unregister() for kqueue poller
add comment about why some args exist
work towards faster start and stop (#131)
Update supervisord.py

Changed priority of error message for reaping an unknown pid from critical to info.
Merge pull request #475 from clustervision/master

Update supervisord.py
Compute delay properly, see comments attached to #263
we no longer need to support py24, so we can use class decorators
fix tests broken by adding fast start/stop features
update my thinking about this