Merge pull request #54 from olleolleolle/build-on-2-2-10

CI: Use rails as git gem with branch 5-2-stable in Gemfile-rails-5-2  to support Ruby 2.2.10

Author: kaspth

gemfiles/Gemfile-rails-5-2

@@ -1,4 +1,6 @@
 source 'https://rubygems.org'
 gemspec path: '..'
 
-gem 'actionpack', '~> 5.2.0'
+git_source(:github) { |repo_name| "https://github.com/#{repo_name}.git" }
+
+gem 'actionpack', '~> 5.2.0', github: 'rails/rails', branch: '5-2-stable'