Added Rubocop harness to enforce Ruby code style
diff --git a/test/rb/Gemfile b/test/rb/Gemfile
index 2d0f8f1..71ea8ea 100644
--- a/test/rb/Gemfile
+++ b/test/rb/Gemfile
@@ -6,3 +6,5 @@
 gem 'rack', '~> 2.2'
 gem 'thin', '~> 1.7', '>= 1.7.2'
 gem 'test-unit', '~> 3.2', '>= 3.2.7'
+
+eval_gemfile File.expand_path("../../lib/rb/Gemfile.linters", __dir__)