Email Customizer for WooCommerce 3.33

* Fixed edge case with some custom wp-admin themes which would interfere with our customizer and render it unusable.

* Fixed the `[ec_custom_field]` shortcode.
* Added the `[ec_get_option]` shortcode. See the documentation here Shortcodes in Email Customizer » cxThemes

-Add 'WC requires' and 'WC tested up to' tags.
-Update all template to latest versions.
-Remove italic styling from addresses.
-Make sure there's no rogue 'woocommerce' text domains.