Add ember-rails
Update jquery-rails as ember dependency
Specify ember-rails variant

Default to :development for all environments. Use :production in
production and staging.
Switch to base ember setup
Enable root elements in serializers
Configure plurals in RESTAdapter
Move notification functions
Catch ember routing errors

Ember expects to have a match to every URL. Catch the error, re-throwing
errors if they don't match the routing error's message.
Add deliveries routes and use pushState
Empty deliveries#new view
Add RecipientsController for creating recipients

Since ember-data will use a POST /users to create records, instead of
the GET /receipts/new currently being used, a different
end point is required to differentiate the behavior between creating a
user as part of the signup process and creating a user who is receing a
delivery (email sent vs no email sent).
Conditionally serialize User#street and User#id

embera-data will use 'null' as a valid id so the attribute must not be
included in order to differentiate between unpersisted records. Since
User#street can be an empty string now, we only want to include it if it
is present.
Setup ember models

Besko.Recipient is an empty extension of Besko.User to have it use the
/recipients end-point.

Besko.Delivery uses a custom store attribute 'nestedAttributesArray' to
work with ActiveRecords `accepts_nested_attributes_for`.
Setup delivery creation using ember

* Bootstrap list of deliverers as embedded JSON using ported parse()
  function.
Update active_model_serializers

Required for how ember-data sideloads records for displaying deliveries
on the index page.
Migrate Besko.Date

Add underscore.js for extending prototypes. Ember does not appear to
expose an API like this.
Sideload users via 'workers' key

May not be future proof as other models may have a 'user' association
that needs to be sideloaded.
Update deliveries#index to use ember

* Updates DeliverySerializer to sideload workers
* Temporarily disables viewing information about receipts belonging to a
  delivery
Port signups to ember
Deliveries sideload workers as users