title: Rails rake db:rollback on Heroku not working. Now I can't add any new migrations
body: <p>I have an app that is working fine locally. At one point I tried installed the Act As Taggable gem, which generated a series of migration files. Now I rolled back locally after we voted against using that gem - but after deploying to heroku, it looks like 5 of these migration files did upload to heroku. </p>
  
  <p>I then ran</p>
  
  <pre><code>`heroku run rake db:migrate'
  </code></pre>
  
  <p>I am now receiving this error</p>
  
  <pre><code>'uninitialized constant AddTaggingsCounterCacheToTags::ActsAsTaggableOn/app/db/migrate/20141107010718_add_taggings_counter_cache_to_tags.acts_as_taggable_on_engine.rb:6:in `up'
  </code></pre>
  
  <p>Now I don't need the  "AddTaggingsCounterCacheToTags" but I definitely need a migration that was supposed to run after this.</p>
  
  <p>Any tips on how I can remove this from the production/heroku server? How I can remove only specific migrations and keep the newest migration I made?</p>
  
  <p>Thanks!</p>