title: Gem "audited-activerecord", "~> 4.0 gives undefined method `audits'
body: <p>I am using:
  Rail 4.1.7
  Ruby 2.1.4</p>
  <p>I just installed <a href="https://github.com/collectiveidea/audited" rel="nofollow noreferrer">Audited GEM</a>:</p>
  <pre><code>gem &quot;audited-activerecord&quot;, &quot;~&gt; 4.0&quot;
  $ rails generate audited:upgrade
  $ rake db:migrate
  </code></pre>
  <p>Model</p>
  <pre><code>class Opportunity &lt; ActiveRecord::Base
      ...
      audited
      ...
  end
  </code></pre>
  <p>And when I run:</p>
  <pre><code>Opportunity.audits.count
  </code></pre>
  <p>I get this error:</p>
  <pre><code>2.1.4 :001 &gt; Opportunity.audits.count
  NoMethodError: undefined method `audits' for #&lt;Class:0x007ff7946656f0&gt;
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/activerecord-4.1.7/lib/active_record/dynamic_matchers.rb:26:in `method_missing'
      from (irb):1
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/railties-4.1.7/lib/rails/commands/console.rb:90:in `start'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/railties-4.1.7/lib/rails/commands/console.rb:9:in `start'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/railties-4.1.7/lib/rails/commands/commands_tasks.rb:69:in `console'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/railties-4.1.7/lib/rails/commands/commands_tasks.rb:40:in `run_command!'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/railties-4.1.7/lib/rails/commands.rb:17:in `&lt;top (required)&gt;'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:247:in `require'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:247:in `block in require'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:232:in `load_dependency'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:247:in `require'
      from /Users/andreucasadella/rails_projects/crm/bin/rails:8:in `&lt;top (required)&gt;'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:241:in `load'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:241:in `block in load'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:232:in `load_dependency'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:241:in `load'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/spring-1.2.0/lib/spring/commands/rails.rb:6:in `call'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/spring-1.2.0/lib/spring/command_wrapper.rb:38:in `call'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/spring-1.2.0/lib/spring/application.rb:183:in `block in serve'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/spring-1.2.0/lib/spring/application.rb:156:in `fork'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/spring-1.2.0/lib/spring/application.rb:156:in `serve'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/spring-1.2.0/lib/spring/application.rb:131:in `block in run'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/spring-1.2.0/lib/spring/application.rb:125:in `loop'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/spring-1.2.0/lib/spring/application.rb:125:in `run'
      from /Users/andreucasadella/.rvm/gems/ruby-2.1.4/gems/spring-1.2.0/lib/spring/application/boot.rb:18:in `&lt;top (required)&gt;'
      from /Users/andreucasadella/.rvm/rubies/ruby-2.1.4/lib/ruby/site_ruby/2.1.0/rubygems/core_ext/kernel_require.rb:54:in `require'
      from /Users/andreucasadella/.rvm/rubies/ruby-2.1.4/lib/ruby/site_ruby/2.1.0/rubygems/core_ext/kernel_require.rb:54:in `require'
      from -e:1:in `&lt;main&gt;'2.1.4
  </code></pre>
  <p>I am using Ruby 2.1.4 and there is a warning sign &quot;Audited may work just fine with a Ruby version not listed above (Latested 2.1.2), but we can't guarantee that it will. If you'd like to maintain a Ruby that isn't listed, please let us know with a pull request.&quot;</p>
  <p>Has anyone experienced this before?</p>