Add a default format if no format is defined in the locale file. Use the same default format as the datepicker gets in the translations partial.

Fixes #3602
While an order_id field exists within inventory_units, we should be able to retrieve these using an association

Fixes #3744
Add regression test for #3744
Associate user in Order `merge!` when possible

Users might be losing their cart changes when they come back but don't
visit either the /cart page or the /checkout

Fixes #3742
Fixes #3736
Bump active merchant to 1.38.1

Fixes #3745
refactored spree stock estimator

Extracted functionality out of #shipping_rates for choosing the default
shipping rate and the for the order shipping rates should be sorted in,
in the interest of overriding said behavior.

Change-Id: Iefcce00f1f2ebfedd565dd3aeb540a6111ffc5b7

Fixes #3748
Fix product paging issue

Fixes #2851
Fixes #3064

Conflicts:
	frontend/app/controllers/spree/taxons_controller.rb
Fix expectations in order/adjustments_spec so that it now passes
Assign location to shipment when importing orders (api) [Fixes #3775]
Should have ability to ensure confirm step is always in progress bar.
Update credit card factory to work any year.
Fix Order#confirmation_required? spec.
Use Time.now.year as Date.year is invalid.
fix page action buttons line wrap in admin
Refactors after_cancel to allow the Mailer method to follow the pattern set in other models.

Allows OrderMailer.cancel_email be sent asynchronously with delayed_job#handel_aynchronously

Fixes #3759
Introduce Order shipping_eq_billing_address method

This might help both frontend and backend to figure out whether the
use_billing checkbox on address forms should be checked. API users
should benefit of it as well

Related to #3758

Conflicts:
	backend/app/views/spree/admin/orders/customer_details/_form.html.erb
[api] skip authentication before filters for states/countries so that frontend's checkout can work even with requires_authentication=true on the API

Conflicts:
	api/app/controllers/spree/api/states_controller.rb

Fixes #3762
Optionally trigger an accessibility build.

Set the WEBDRIVER environment variable to `accessible`

[Finishes #3374]

Related to #3414
Fix accessibility errors in search input.

[#3374]

Related to #3414
Add inaccessible tag to failing features.

Related to #3414