Add NetBSD 6.1.3 templates.
Merge pull request #900 from tsahara/netbsd-613-amd64

Add NetBSD 6.1.3 templates.
Exit with a non-zero exit code if something goes wrong
Merge pull request #901 from phusion/master

Exit with a non-zero exit code if something goes wrong
Correctly escape commands passed to 'vewee <provider> ssh'.
Fix usage of SSH key in `veewee <provider> ssh`
Merge pull request #902 from phusion/master

Correctly escape commands passed to 'veewee <provider> ssh', properly use SSH key