Yet another breadcrumbs api

Born out of frustration with existing breadcrumb projects, here's yet another breadcrumbs API.

The architectural design is based on the Crumbs module and References hierarchy (sandbox; works with Menu position).

The main idea is to recursively build a hierarchy of drupal paths, from the current page up to the the root (i.e. the frontpage). Once the hierarchy has been created, it is used to overwrite core's breadcrumbs (using drupal_set_breadcrumb()).

Additionally, the module marks any menu items in the hierarchy as active (thanks to menu_tree_set_path()); this can be turned off if needed.

Dependencies:

• CTools: plugins functionality

Notes:

• It's an API module. Doesn't do much by itself.
• Can be extended fairly easily with ctools plugins; see "plugins" folder for basic examples
• Widely untested, and not finished... Use at own risk.