Add Rails release to ActiveRecord::Migration

plugins/messages/db/migrate/20090120184410_create_messages.rb.skip

@@ -5,7 +5,7 @@
 # attempt to create an already existing messages table.
 #
 # extracted from 20090120184410_road_to_version_three.rb
-class CreateMessages < ActiveRecord::Migration
+class CreateMessages < ActiveRecord::Migration[4.2]
   def self.up
     create_table :messages do |t|
       t.references :sender

plugins/messages/db/migrate/20160226000000_add_email_to_message.rb

@@ -1,4 +1,4 @@
-class AddEmailToMessage < ActiveRecord::Migration
+class AddEmailToMessage < ActiveRecord::Migration[4.2]
   def change
     add_column :messages, :salt, :string
     add_column :messages, :received_email, :binary, :limit => 1.megabyte