Do not vendor cookbooks using Berkshelf anymore

Instead, use the Berkshelf support in knife-solo and the
vagrant-berkshelf plugin on Vagrant

Vagrantfile

@@ -27,6 +27,13 @@ Vagrant.configure(2) do |config|
     override.ssh.port = 22
   end
 
+  if Vagrant.has_plugin?("vagrant-berkshelf")
+    config.berkshelf.enabled = true
+  else
+    puts "Install vagrant-berkshelf:\n  vagrant plugin install vagrant-berkshelf"
+    exit 1
+  end
+
   # Disable automatic box update checking. If you disable this, then
   # boxes will only be checked for updates when the user runs
   # `vagrant box outdated`. This is not recommended.
@@ -84,7 +91,7 @@ Vagrant.configure(2) do |config|
 
   config.vm.provision :chef_zero do |chef|
     chef.version                            = '14.11.21'
-    chef.cookbooks_path                     = ['cookbooks', 'site-cookbooks']
+    chef.cookbooks_path                     = ['site-cookbooks']
     chef.data_bags_path                     = 'data_bags'
     chef.roles_path                         = 'roles'
     chef.node_name                          = "vagrant-node"