Add plugin subcommand
Add plugin subcommand

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