You're viewing the documentation for the experimental version of Vagrant (the 1.x series). The current stable series is 1.0.x and the documentation can be found here. You can learn more about the Vagrant versioning scheme here.
Configuration key: config.vm.provision
This configuration directive may be used multiple times and configures a provisioner for the virtual machine. If this is used multiple times, the provisioners are called in order. Please read the page documented provisioners to learn about provisioning your virtual machine.