title: Rails: "t.references" not working when creating index
body: <pre><code>class CreateBallots &lt; ActiveRecord::Migration
    def change
      create_table :ballots do |t|
        t.references :user
        t.references :score
        t.references :election
        t.string :key
        t.timestamps
      end
      add_index :ballots, :user
      add_index :ballots, :score
      add_index :ballots, :election
    end
  end
  </code></pre>
  
  <p>results in:</p>
  
  <pre><code>SQLite3::SQLException: table ballots has no column named user: CREATE  INDEX "index_ballots_on_user" ON "ballots" ("user")/home/muhd/awesomevote/db/migrate/20130624024349_create_ballots.rb:10:in `change'
  </code></pre>
  
  <p>I thought <code>t.references</code> was supposed to handle that for me?</p>