Add more information for cloud-init options in docs
Add more information for cloud-init options in docs

chrisroberts/vagrant,sni/vagrant,chrisroberts/vagrant,mitchellh/vagrant,marxarelli/vagrant,marxarelli/vagrant,sni/vagrant,marxarelli/vagrant,chrisroberts/vagrant,mitchellh/vagrant,mitchellh/vagrant,sni/vagrant,marxarelli/vagrant,mitchellh/vagrant,chrisroberts/vagrant,sni/vagrant