[#720] Add acts-as-taggable-on gem and migration for tag support

As per the gem docs, 2.1.0 is the last Rails 2.x compatable version

Gemfile

@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 source :rubygems
 
 gem "rails", "2.3.14"
@@ -7,6 +8,7 @@ gem "i18n", "~> 0.4.2"
 gem "rubytree", "~> 0.5.2", :require => 'tree'
 gem "rdoc", ">= 2.4.2"
 gem "liquid", "~> 2.3.0"
+gem "acts-as-taggable-on", "2.1.0"
 # Needed only on RUBY_VERSION = 1.8, ruby 1.9+ compatible interpreters should bring their csv
 gem "fastercsv", "~> 1.5.0", :platforms => [:ruby_18, :jruby, :mingw_18]
 

db/migrate/20111125191432_acts_as_taggable_on_migration.rb

@@ -0,0 +1,29 @@
+class ActsAsTaggableOnMigration < ActiveRecord::Migration
+  def self.up
+    create_table :tags do |t|
+      t.column :name, :string
+    end
+    
+    create_table :taggings do |t|
+      t.column :tag_id, :integer
+      t.column :taggable_id, :integer
+      t.column :tagger_id, :integer
+      t.column :tagger_type, :string
+      
+      # You should make sure that the column created is
+      # long enough to store the required class names.
+      t.column :taggable_type, :string
+      t.column :context, :string
+      
+      t.column :created_at, :datetime
+    end
+    
+    add_index :taggings, :tag_id
+    add_index :taggings, [:taggable_id, :taggable_type, :context]
+  end
+  
+  def self.down
+    drop_table :taggings
+    drop_table :tags
+  end
+end