[2.2] Make updater set parent backorder status

Closes #6494
Prevented warnings when countries is empty in shipping methods.

Stopped this erros:

PHP Warning:  array_intersect(): Argument #1 is not an array in
wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-shipping-method.php
on line 182
PHP Warning:  in_array() expects parameter 2 to be array, null given in
wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-shipping-method.php
on line 194
Changelog bump for 9f74996 changes
Prevent warnings in WC_Shipping_Method::is_available() when exclude countries
[2.2] use mb_strtolower() in wc_get_order_status_name()
dump changelog for 117dcf6
[2.2] fixed edit account page fields, closes #6577
Fix potential error if variation doesn't exist
[2.2] Fix refund date.

Fixes #6499
$cart_totals should be checked to see if its an array

Closes #6496
Register post types before each unit test

Fixes #6501

see
https://core.trac.wordpress.org/changeset/29860/trunk/tests/phpunit/incl
udes/testcase.php, apparently we were #doingitwrong  🙈
Prevented warnings when countries is empty in shipping methods.

Stopped this erros:

PHP Warning:  array_intersect(): Argument #1 is not an array in
wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-shipping-method.php
on line 182
PHP Warning:  in_array() expects parameter 2 to be array, null given in
wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-shipping-method.php
on line 194

@mikejolley
Prevent warnings in WC_Shipping_Method::is_available() when exclude countries
In the US address format, use state code rather than the full state name.
[2.2] Prevent notice if meta is not set Closes #6514
Use mb_strtolower to prevent issues with unicode chars

Fixes #6525
Make cart total consider taxes

Fixes #6522
[2.2] Fix /shop/ base URL Non Latin issue with url decode

Fixes #6512
Fix conflict
Turn caching back on