title: db:migrate error during rake on Rails 4.0.0
body: <p>Working on project in Rails 4.0.0, ruby 1.9.3p392 (2013-02-22 revision 39386) [x86_64-darwin10.8.0], with Rake 10.1.1</p>
  
  <p>I was working on an app for a class in Rails, I made an error and deleted the changes made while in Git. When I went to redo the project, and ran the rake DB migration, I was given the following error message:</p>
  
  <pre><code>Joses-MacBook-Air:crumblr JRV$ rails generate migration CreateHearts Post_id:integer
    invoke  active_record
    create    db/migrate/20140120235500_create_hearts.rb
  Joses-MacBook-Air:crumblr JRV$ bundle exec rake db:migrate
  ==  CreateHearts: migrating ===================================================
  -- create_table(:hearts)
  rake aborted!
  An error has occurred, this and all later migrations canceled:
  
  SQLite3::SQLException: table "hearts" already exists: CREATE TABLE "hearts" ("id" INTEGER        PRIMARY KEY AUTOINCREMENT NOT NULL, "Post_id" integer) /usr/local/rvm/gems/ruby-1.9.3-  p392/gems/sqlite3-1.3.8/lib/sqlite3/database.rb:91:in `initialize'
  4.0.0/lib/active_record/railties/databases.rake:42:in `block (2 levels) in &lt;top    (required)&gt;'
  Tasks: TOP =&gt; db:migrate
  (See full trace by running task with --trace)
  </code></pre>
  
  <p>How do I get rid of the old table reference?</p>