added PoolContext object to share state within pool's threads
moved thread logic to use PoolContext
updated tests
moved process logic to use PoolContext
completed process and tests
if no workers are running do not wait full time
added expired_workers
Merge branch 'master' of github.com:noxdafox/pebble
added atexit in child process
cleanup and re-organization
more code cleanup
channel closed by atexit
fixed join
more code cleanup
fix bug in task schedule
coroutine experiment no2
remove exception handling in schedule_task
foo
task_scheduler can raise IOError
worker manager now spawns processes as well