Auto-restart the agent with forking and parent supervision
Make sure to kill the child process before exiting the parent
put auto-restart behind a command-line flag
Merge branch 'master' into autorestart

Conflicts:
	daemon.py
A SIGUSR1 will trigger an autorestart (exit code 5)
Add some tests around auto-restarting
Merge branch 'master' into autorestart
make the auto-restart tests less flaky
give more time for the agent to start on travis
only auto-restart when the option is on
Merge branch 'master' into autorestart

Conflicts:
	agent.py
	checks/collector.py
	config.py
	daemon.py
disable autorestarat tests because they are too flaky for travis
Merge pull request #319 from DataDog/autorestart

Auto-restart the agent