add missing translation editing_country

Closes #5736
fix n+1 for variants index action
Closes #5722
include product for variant stock items update

Closes #5720
refactor taxons controller in backend to follow DRY and break update action into number of smaller methods

Closes #5727
fix n+1 for admin product images

Closes #5723
Revert "fix n+1 for admin product images"

This reverts commit 2acb334efd85c5e0467a1db64938cf28f08d8fe8.
Add scoping when matching to orders tax_zone to find possible relevant zones

Ensure default tax zone

Add cached_kind attribute to Zone

Add associations to countries and states through zones - pluck ID's to optimize expensive Spree::Zone#contains? method

Fix removing default tax from orders outside the default tax zone issue

Set up a Zone#kind in the db instead

Fixes #5650
Clicking around works better than js to fade away datepicker.
Prevent ordering unpersisted product properties. Fixes #5703
Stock Items n+1 update.

add params for method args

variant stock includes

fixes #5721
Show order state changes

Move state_changes to own controller. Move translations to AR key

Translate state change names, tidy up controller

Fixes #5696
Cleanup state change history for bootstrap.
Fix grammar of error message. Fixes #5735
AdjustmentSource tests moved into a shared example.

has_many and before_destroy declarations moved into concern.
This file should not have made it back in during merge conflict.
Fix an incorrect inverse_of

This breaks things in strange ways...
AdjustmentSource tests moved into a shared example.

has_many and before_destroy declarations moved into concern.

fixes #5731
Fixes to run tests in windows.

http://stackoverflow.com/questions/23022258/tzinfodatasourcenotfound-error-starting-rails-v4-1-0-server-on-windows

http://stackoverflow.com/questions/10154670/system-cannot-find-the-path-specified-when-running-rake-test-app-with-spree

Fixes #5734
Merge pull request #5747 from gmacdougall/fix-bad-inverse

Fix an incorrect inverse_of
Eager load associations in InventoryUnitBuilder

Everything here will be needed inside coordinator, perhaps we could have
some sort of `assert_no_queries` examples on the build to see whether
and when we miss any records

fixes #5690