Vendor the chef-gem software definition

Source:
https://github.com/opscode/omnibus-software/blob/4f92644e5aa0e728b34b82b21170d553826d5f41/config/software/chef-gem.rb

config/software/chef-gem.rb

+#
+# Copyright:: Copyright (c) 2012-2014 Chef Software, Inc.
+# License:: Apache License, Version 2.0
+#
+# 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.
+#
+
+name "chef-gem"
+default_version "11.12.2"
+
+dependency "ruby"
+dependency "rubygems"
+
+build do
+  gem "install chef -n #{install_dir}/embedded/bin --no-rdoc --no-ri -v #{version}"
+end