add uniqueness validation in spree preference
Order history should be reverse chronological. Fixes #5024
return 204 for PUT /orders/empty
Fix spec for ruby 2.0

With Ruby 2.0.0 p451 this was giving:

    expected: 95.17
         got: #<BigDecimal: 95.17000000000001>
Add roadmap url. Fixes #5025
Merge pull request #5032 from HoyaBoya/fix/empty_order_204_response

return 204 for PUT /orders/empty
allow specifying Kaminari page_method_name

only define custom page method if page_method_name != page to avoid recursion
Fixes #5035
Use the proper flash

This is not a success
Fixes #5034
Update Google Analytics

Updates GA tracking code to support Display Advertising. See: https://support.google.com/analytics/answer/2444872 for more.
Fixes #5030
Fix order merging. Fixes #5028
Merge pull request #4999 from vinsol/preference_validation

add uniqueness validation in spree preference
Wait ajax request a bit for backend spec fix
Refactor stock related models to deal with inventory units.

Prior to this change, stock related service objects (coordinator, packer,
prioritizer, package, adjuster) were tightly coupled to orders and line
items, such that they would only create a set of shipments for the set
of line items for an order.

This change makes those objects work with inventory units, which enables
future enhancements that would create shipments for an order that are
not necessarily tied to the initial purchase (e.g. upcoming exchanges
work).