Require login, associate lunches to current user
Generate LunchMailer with a data_update_notification view

This is the result of running:
rails generate mailer LunchMailer data_update_notification
Add email configuration for development
Change the sender, message, and recipient in LunchMailer
Modify the views: add a new sentence at the end
Include a lunch count in the email
Send the user an email when they update their lunch data
Change the subject of the email
Add letter_opener gem and use it as the default delivery method
Include lunch dates in email, and remove content generated by 'rails generate'
Merge branch 'action_mailer'

Conflicts:
	app/controllers/application_controller.rb
Merge branch 'master' of github.com:wdi-hk-sep-2014/PepperLunchClone

Conflicts:
	Gemfile.lock