Add after_fork callbacks, close_stdio flag, and subprocess renaming.
Untangle remote application control and services.
Add restore-all-traps flag.
Add process pool.

Conflicts:
	lib/dont-stall-my-process/remote/remote_application.rb
Remove unused DRbServiceRegistry.
Final fixups, cache local proxies, put klass name in subprocess name.
Ignore untrappable signals.
Make it possible to manually end nested proxies.
Add skip_at_exit_handlers flag.
Fix the DRb stop service call and parent notification.