Scalability Pro 5.53

* Fixed a bug in the new transient cache where with some db configs it could keep on redefining the table

* Updated stored reference list tables from WP updates
- hopefully this doesn't need to happen too often, maybe I could just reference the constructor of the parent somehow to run the hash check

version number bumped for new deployment system test

* Moved all 'query' filters into special handlers to ensure they only run when required, e.g. when cron, when is_admin, or when front-end depending on the filter
* Fixed slow query log - it was still possible for this to be running on every query
* Removed code that was spoofing the new install and has_products
- this is instead replaced by our own post count cache
- the previous method of spoofing 1 item for each post_status was being cached and used elsewhere where it wasn't useful
- this method guarantees accurate and sensible counts
- the cache is only wiped at night time, so you can import all day without the posts being recounted
* Added a new Clear Cache button to the Imports tab next to the defer term counting option
* Changed Settings plugin name to just Scalability Pro (rather than Scalability Pro Plugin)
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* TODO:
* Add button to enable all recommended options
* Remove initial install override

Updated plugin updater to look at superspeedyplugins.com

* Added new SPRO_PREVENT_WPAI_DUP_CHECK definition
- setting this to true can help speed up WP All Import if you have large imports
- this seems to be dependent on your config for your 'unique key' which is normally automated
* Fixed bug with fixing Woo Onboarding code
- the has_products function was fixed previously, now the is_new_install is properly fixed
- previously the fix had only been added to some admin pages, this fix now stops that slow code running on WP All Import batches too
* Altered wp-admin > Optimise Woo products list to instead Remove Woo Product Category dropdown
- the code previously altered the code to only list the first level of categories, but was no longer working
- now this code just removes that dropdown completely
- with the recent update to Super Speedy Search you can search for categories instead

* Improved Slow Query Log so it captures info more reliably
* Fixed bug that prevented slow query log running if no db.php existed

* Added 2 hour transient cache for reading changelog files from our server
- this will speed up wp-admin slightly and prevent the 403 forbidden error messages some have been getting when trying to run plugin updates

* Option to cache post counts for admin pages created
- this has been separated out from defer term counts as a separate option, but it's still in the import tab because it helps most with admins running imports a lot
- option has also been updated to exclude shop_order post types from the cache since order statuses change frequently and admins need to see what items remain to be done

Fixed bug in switching off slow sql profiling

* Added new detection of unnecessary GROUP BY when LIMIT 0,1 is being used
- this seems to happen in imports and causes a table scan of wp_posts, so this should result in a good boost for imports on large sites
* Added further improvement for 'defer term counting'
- when a new item is published, that post types cache is wiped
- this leads to slower imports since an entire recount can happen after every import
- The change has modified this query to fetch data from our own cache table which stores the counts for 24 hours if you enable the defer term counting option
* Added Optimize Product Attributes Lookup functionality to the Imports tab
- WooCommerce maintains the product attributes table EVEN IF you deselect to use it
- One outstanding issue here on larger sites is the SQL where they check WHERE product_id = 984353 OR product_or_parent_id = 984353;
- only the product_or_parent_id needs to be checked in this case and then an index gets used
- This functionality alters this SQL query if you enable the option on the Imports tab