Rename node main script to avoid confusion
Update exit code
Change post-receive hook to pre-receive hook, this allows to deny a push
Add log support for silent commands
Add support for bower
Split scripts to avoid unnecessary sudo

Now, the git user runs node-deploy-branch.sh, and needs some root privileges to:
1. Restore rights for www-data and node (chrights.sh).
2. Start/stop the main node application (node-app-manager.sh).