Update Ruby on Rails documentation (5.2.0)

lib/docs/scrapers/rdoc/rails.rb

@@ -56,23 +56,27 @@ module Docs
     options[:attribution] = ->(filter) do
       if filter.slug.start_with?('guides')
         <<-HTML
-          &copy; 2004&ndash;2017 David Heinemeier Hansson<br>
+          &copy; 2004&ndash;2018 David Heinemeier Hansson<br>
           Licensed under the Creative Commons Attribution-ShareAlike 4.0 International License.
         HTML
       else
         <<-HTML
-          &copy; 2004&ndash;2017 David Heinemeier Hansson<br>
+          &copy; 2004&ndash;2018 David Heinemeier Hansson<br>
           Licensed under the MIT License.
         HTML
       end
     end
 
+    version '5.2' do
+      self.release = '5.2.0'
+    end
+
     version '5.1' do
-      self.release = '5.1.4'
+      self.release = '5.1.6'
     end
 
     version '5.0' do
-      self.release = '5.0.6'
+      self.release = '5.0.7'
     end
 
     version '4.2' do