Added a README.txt, Changed $new to $children_operations for more readability, and fixed a few typos in the module description.

Added the Comment ID to the comment by merlinofchaos where he cites the use of page_manager_variant_operations_alter() by panels everywhere.

Removed trailing spaces and some typos and now panels_breadcrumbs passes successfuly Code Review by Coder Module.

Added a few more comments to the code, and also added a checkbox that (de)activates breadcrumbs for a given variant.