删除冗余的迁移文件

app/models/message.rb

@@ -40,6 +40,7 @@ class Message < ActiveRecord::Base
   # 课程/项目 消息
   has_many :course_messages, :class_name =>'CourseMessage', :as => :course_message, :dependent => :destroy
   has_many :forge_messages, :class_name => 'ForgeMessage', :as => :forge_message, :dependent => :destroy
+  has_many :org_activities, :class_name => 'OrgActivity', :dependent => :destroy
   has_many :at_messages, as: :at_message, dependent: :destroy
 
   has_many :ActivityNotifies,:as => :activity, :dependent => :destroy

db/migrate/20151230015225_add_quotes_to_messages.rb

@@ -1,4 +0,0 @@
-class AddQuotesToMessages < ActiveRecord::Migration
-  def change
-  end
-end