Vendor the external cookbooks

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

cookbooks/git/libraries/matchers.rb

@@ -0,0 +1,16 @@
+if defined?(ChefSpec)
+  ChefSpec.define_matcher(:git_client)
+  ChefSpec.define_matcher(:git_service)
+
+  def set_git_config(resource_name) # rubocop:disable Style/AccessorMethodName
+    ChefSpec::Matchers::ResourceMatcher.new(:git_config, :set, resource_name)
+  end
+
+  def install_git_client(resource_name)
+    ChefSpec::Matchers::ResourceMatcher.new(:git_client, :install, resource_name)
+  end
+
+  def install_git_service(resource_name)
+    ChefSpec::Matchers::ResourceMatcher.new(:git_service, :install, resource_name)
+  end
+end