Issue 5661: filter params
#2906 - Set reviews count in tab to only count actual reviews

Nested comments shouldn’t be treated as reviews. This addresses that by
using `$product->get_rating_count()` to determine the correct number of
reviews, instead of get_comments_number.

It can be filtered using the new `woocommerce_product_reviews_count`
filter.
#4459 - Add filters for product_list_widget before / after

2 new filters introduced:

* `woocommerce_before_widget_product_list`
* `woocommerce_after_widget_product_list`
#5850 - Add QR code to API credentials

This uses https://github.com/jeromeetienne/jquery-qrcode for generating
the QR code.

This is what it looks like:

![see screen shot](http://cld.wthms.co/11wpb+)

It’s small, **but**, it scans perfectly without any issues.
Remove previously added filter, not necessary
Split up save_tax_rates() method
Merge pull request #6798 from bryceadams/patch-2906

#2906 - Set reviews count in tab to only count actual reviews
Redo construct and move settings/html to separate files
Fix refund class
Corrected format_ methods
Moved delete tax rate rule
Added method for expanding postcode ranges
Tax rate importer parse error
Optimise tax rate importer and use same code as tax settings class
Move widget registration to own function/file - avoid register_widget in class files
combine city and postcode save logic
Only enqueue/localize on profile page
#5537 - Fix bulk edit overlap, bulkedit improvements
Change remove_order_items subqueries to inner joins.
Closes #6804
Hat tip Jason @ WPEngine
#6026 - Introduction of Sort Code 'locale' for BACS

In the admin, it will use the store’s base country to determine the
term for ‘Sort Code’.

In the front-end, it will use the customer’s billing country to
determine the term for ‘Sort Code’.

In all cases, if a locale does not have a sortcode label set, it will
use ‘Sort Code’.

**Locales have been added for:**
* AU
* CA
* IE
* IN
* IT
* NZ
* SE
* US
* GB
* ZA

But may need adjusting based on user feedback.