title: Error after rake db:migrate command: rake aborted! NoMethodError: undefined method `accept' for nil:NilClass
body: <p>Once i type rake db:migrate i receive this message </p>
  
  <pre><code>C:/Ruby23-x64/lib/ruby/gems/2.3.0/gems/activesupport-4.0.0/lib/active_support/values/time_zone.rb:282: warning: circular argument reference - now
  
  rake aborted!
  
  NoMethodError: undefined method `accept' for nil:NilClass
  C:3:in `rescue in map'
  C:-1:in `map'
  NoMethodError: undefined method `accept' for nil:NilClass
  C:-1:in `map'
  Tasks: TOP =&gt; db:migrate
  </code></pre>
  
  <p>The following is my GemFile</p>
  
  <pre><code>source 'https://rubygems.org'
  
  # Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
  gem 'rails', '4.0.0'
  
  # Use mysql as the database for Active Record
  gem 'mysql2'
  
  gem 'activerecord-mysql2-adapter'
  
  # Use SCSS for stylesheets
  gem 'sass-rails', '~&gt; 4.0.0'
  
  # Use Uglifier as compressor for JavaScript assets
  gem 'uglifier', '&gt;= 1.3.0'
  
  
  # Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
  gem 'jbuilder', '~&gt; 1.2'
  
  group :doc do
    # bundle exec rake doc:rails generates the API under doc/api.
    gem 'sdoc', require: false
  end
  </code></pre>
  
  <p>and the following is my database.yml</p>
  
  <pre><code>development:
    adapter: mysql2
    encoding: utf8
    database: test_app_development
    pool: 5
    username: root
    password: password
    host: localhost
  </code></pre>
  
  <p>Before adding activerecord-mysql2-adapter to my gem files I got this error : active record::conecction not established webbrick 
  but after i added that gem it was fine (This was done before creating a database). A lot of forums online indicate that this gem is the origin of my problem and now when i remove it after creating a database I get the following error : Specified 'mysql2' for database adapter, but the gem is not loaded. Add <code>gem 'mysql2'</code> to your Gemfile.</p>
  
  <p>I am running rails 4.0.0 on ruby 2.3.0 on windows 
  Thanks a lot for your help</p>