This commit performs salt provisioning setup by adding salt master to
the salt VM and salt minion to all VMs. An /etc/hosts entry for the salt
master is added using a shell provisioner. No salt executions are
performed yet.
This commit defines a multi machine Vagrant setup with internal
networking and the gnuviechadmin Git repositories mounted as shared
folders inside the corresponding virtual machines.
The contained bootstrap.sh clones all Git repositories and runs Vagrant
in the correct order.
