downgrade rack

Gemfile

@@ -5,6 +5,8 @@ git_source(:github) {|repo_name| "https://github.com/#{repo_name}" }
 # Specify your gem's dependencies in yandex-checkout.gemspec
 gemspec
 
+gem 'evil-client', git: 'https://github.com/paderinandrey/evil-client.git'
+
 group :development, :test do
   gem 'pry',        platform: :mri
   gem 'pry-byebug', platform: :mri