added mandrill-api gem
added configuration details to development.rb
added configuration to both development.rb again
rails g UserMailer
added welcome_email to UserMailer
added sample mailing templates
added routes and controller logic to send welcome email
I can now send email to user via Mandrill succesfully
added mandrill configuration to both development and productoin environment
simplified photos#create in photos_controller
Merge branch 'email-notification'