This commit introduces a banner that notifies and prompts users to upgrade their WordPress and/or PHP if they are outdated and not part of the minimum required versions going into WooCommerce 3.7.
* Add backward compatible function wp_check_php_version for sites running WP version smaller than 5.1
* Refactor some messaging, move widget to top of WC dashboard widgets, add buttons linking out to WP pages with instructions.
* Add missing variables for adding nag class
* Add styling to dashboard widget
* Rework css to use exclamation instead
* Clean up widget, make sure no widget is registered when dismissed. Add banner that links to widget and make it dismissable.
* Update constant to reflect minimum requirements.
* Don't show banner. Fix undefined variable.
* Remove dashboard widget
* Update banner link to docs site
* Add link to docs page where instructions live for updating
* Change button text
* Add UTM params to docs link
* Moved the msg logic from template to php file.
* Bail out early when PHP and WP versions are ok.
* Added missing translation functiog
* Extracted notice function from reset_admin_notices.
To follow suit with other similar functions in the file.
* Synchronize fetching of WP version.
* Removed unused functions.
* Corrected indent.
* Reduce number of variables and fixed coding standards
* Updated wording of the notice.
Rodrigo Primo
Gerhard Potgieter