Merge pull request #548 from soyuka/master

Fix #543
(upstart) Reload user environnement on sudo
Merge branch 'master' of https://github.com/Unitech/pm2
Startup refractor
- replaced all instances of `sudo` by native `su`
- startup scripts are called with su -c "cmd"
- improved code (less repetitions)
- user is added to the init script but isn't the one that fix permission and put the upstart script
Merge pull request #555 from soyuka/sudofix

Startup refractor
edits
update README to describe PM2 API
Deep Agent update
Clean ProcessContainer
reverse test
bump
display N/A if date is not available

fix #545
bump fix
bump travis
Merge pull request #563 from rlidwka/n_a

display N/A if date is not available
fix #545
bump Interactor
Fix #558