Use require_relative introduced in Ruby 1.9.2

The new `require_relative` command is much shorter and easier to read
then the previous:

    -require File.expand_path('../config/application', __FILE__)
    +require_relative 'config/application'

Rakefile

@@ -2,7 +2,7 @@
 # Add your own tasks in files placed in lib/tasks ending in .rake,
 # for example lib/tasks/capistrano.rake, and they will automatically be available to Rake.
 
-require File.expand_path('../config/application', __FILE__)
+require_relative 'config/application'
 
 Openfoodnetwork::Application.load_tasks
 

config/application.rb

@@ -1,4 +1,4 @@
-require File.expand_path('../boot', __FILE__)
+require_relative 'boot'
 
 require 'rails/all'
 

config/environment.rb

@@ -1,5 +1,5 @@
 # Load the rails application
-require File.expand_path('../application', __FILE__)
+require_relative 'application'
 
 # Initialize the rails application
 Openfoodnetwork::Application.initialize!

lib/tasks/dev.rake

@@ -5,8 +5,8 @@ namespace :openfoodnetwork do
 
     desc 'load sample data'
     task :load_sample_data => :environment do
-      require File.expand_path('../../../spec/factories', __FILE__)
-      require File.expand_path('../../../spec/support/spree/init', __FILE__)
+      require_relative '../../spec/factories'
+      require_relative '../../spec/support/spree/init'
       task_name = "openfoodnetwork:dev:load_sample_data"
 
       # -- Shipping / payment information

script/delayed_job

@@ -1,5 +1,5 @@
 #!/usr/bin/env ruby
 
-require File.expand_path(File.join(File.dirname(__FILE__), '..', 'config', 'environment'))
+require_relative '../config/environment'
 require 'delayed/command'
 Delayed::Command.new(ARGV).daemonize

script/rails

@@ -2,5 +2,5 @@
 # This command will automatically be run when you run "rails" with Rails 3 gems installed from the root of your application.
 
 APP_PATH = File.expand_path('../../config/application',  __FILE__)
-require File.expand_path('../../config/boot',  __FILE__)
+require_relative '../config/boot'
 require 'rails/commands'

spec/spec_helper.rb

@@ -8,7 +8,7 @@ Knapsack.tracker.config({enable_time_offset_warning: false}) unless ENV['CI']
 Knapsack::Adapters::RSpecAdapter.bind
 
 ENV["RAILS_ENV"] ||= 'test'
-require File.expand_path("../../config/environment", __FILE__)
+require_relative "../config/environment"
 require 'rspec/rails'
 require 'capybara'
 require 'database_cleaner'

test/test_helper.rb

@@ -1,5 +1,5 @@
 ENV["RAILS_ENV"] = "test"
-require File.expand_path('../../config/environment', __FILE__)
+require_relative '../config/environment'
 require 'rails/test_help'
 
 class ActiveSupport::TestCase