Vendor the external cookbooks

Knife-Zero doesn't include Berkshelf support, so vendoring everything in
the repo is convenient again

cookbooks/homebrew/recipes/cask.rb

@@ -0,0 +1,26 @@
+#
+# Cookbook:: homebrew
+# Recipes:: cask
+#
+# Copyright:: 2014-2016, Chef Software, Inc <legal@chef.io>
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+homebrew_tap 'caskroom/cask'
+
+directory '/Library/Caches/Homebrew/Casks' do
+  owner homebrew_owner
+  mode '775'
+  only_if { ::Dir.exist?('/Library/Caches/Homebrew') }
+end