Default Class Wrapper System

[jasperf]

This pull request introduces a comprehensive default wrapper class system for banners in the Banner Container Plugin, enhancing styling options and user experience. The changes include the addition of default CSS classes for all banner locations, an additive class system for custom styling, and updates to the admin interface and codebase to support these enhancements.

Major Enhancements to Wrapper Class System:

• Default Wrapper Classes: Each banner location now has unique default CSS classes, such as iwz-head-banner for top-of-page banners and iwz-footer-banner for footer banners. These defaults are automatically applied, ensuring consistent styling across all locations. [1] [2] [3]
• Additive Class System: Custom CSS classes can now be added alongside default classes, rather than replacing them, allowing for greater flexibility in styling. [1] [2]

Updates to Documentation:

• Changelog and README: Documentation has been updated to reflect the new wrapper class system, including details on default classes, the additive system, and example usage. [1] [2] [3]

Codebase Enhancements:

• Banner Settings: Default wrapper classes are now dynamically assigned based on location in class-iwz-banner-container-settings.php. Admin interface descriptions have been updated to reflect these changes. [1] [2] [3]
• Banner Rendering: The wrap_banner_html method has been updated to include location-based default classes during banner rendering, ensuring consistent application of styles. [1] [2] [3]

These changes improve the plugin's usability, maintain backward compatibility, and provide a more robust framework for banner customization.