Clean Up Gemfile

The Gemfile of a current Rails project looks like this:

    source 'https://rubygems.org'
    
    # Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
    gem 'rails', '4.0.0.rc1'
    
    # Use postgresql as the database for Active Record
    gem 'pg'
    
    # Use SCSS for stylesheets
    gem 'sass-rails', '~> 4.0.0.rc1'
    
    # Use Uglifier as compressor for JavaScript assets
    gem 'uglifier', '>= 1.3.0'
    
    # Use CoffeeScript for .js.coffee assets and views
    gem 'coffee-rails', '~> 4.0.0'
    
    # See https://github.com/sstephenson/execjs#readme for more supported runtimes
    # gem 'therubyracer', platforms: :ruby
    
    # Use jquery as the JavaScript library
    gem 'jquery-rails'
    
    # Turbolinks makes following links in your web application faster. Read more: https://github.com/rails/turbolinks
    gem 'turbolinks'
    
    # Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
    gem 'jbuilder', '~> 1.0.1'
    
    group :doc do
      # bundle exec rake doc:rails generates the API under doc/api.
      gem 'sdoc', require: false
    end
    
    # Use ActiveModel has_secure_password
    # gem 'bcrypt-ruby', '~> 3.0.0'
    
    # Use unicorn as the app server
    # gem 'unicorn'
    
    # Use Capistrano for deployment
    # gem 'capistrano', group: :development
    
    # Use debugger
    # gem 'debugger', group: [:development, :test]
    
Figure out which sections should be adjusted in current project