终端进入到 rails app 目录后总是提示

RVM used your Gemfile for selecting Ruby, it is all fine - Heroku does that too,
you can ignore these warnings with 'rvm rvmrc warning ignore /home/johnlu/rails_projects/mysampleapp/Gemfile'.
To ignore the warning for all files run 'rvm rvmrc warning ignore allGemfiles'.

Gemfile 的内容为：

source 'http://ruby.taobao.org'
ruby '2.0.0'

gem 'rails', '4.0.0'

group :development, :test do
  gem 'sqlite3', '1.3.7'
  gem 'rspec-rails', '2.13.1'
end

group :test do
  gem 'selenium-webdriver', '2.0.0'
  gem 'capybara', '2.1.0'
end

gem 'sass-rails', '4.0.0'
gem 'uglifier', '2.1.1'
gem 'coffee-rails', '4.0.0'
gem 'jquery-rails', '2.2.1'
gem 'turbolinks', '1.1.1'
gem 'jbuilder', '1.0.2'

group :doc do
  gem 'sdoc', '0.3.20', require: false
end

group :production do
  gem 'pg', '0.15.1'
end

系统：Ubuntu 12.04