INDY-1181: Suggest amd64 arch for packer build / fix box name

Signed-off-by: Beat Christen <[email protected]>

environment/vagrant/training/vb-multi-vm/TestIndyClusterSetup.md

@@ -51,11 +51,11 @@ Help](https://www.vagrantup.com/docs/cli/)
 This downloads a Vagrant "box" for Ubuntu 16.04 (LTS) onto your PC.  Think of
 your "box" as an VM image, similar to an AWS AMI or a VMware OVA.
 
-> **Tip:** Try this if you get the error "The box 'bento/ubuntu-1604' could not be found"
+> **Tip:** Try this if you get the error "The box 'bento/ubuntu-16.04' could not be found"
 >   * `git clone https://github.com/chef/bento`
 >   * `cd bento/ubuntu`
->   * `packer build ubuntu-16.04-i386.json` # adjust for your environment
->   * `vagrant box add ../builds/ubuntu-16.04-i386.virtualbox.box --name bento/ubuntu1604`
+>   * `packer build ubuntu-16.04-amd64.json` # adjust for your environment
+>   * `vagrant box add ../builds/ubuntu-16.04.virtualbox.box --name bento/ubuntu-16.04`
 
 #### Warning