Clarify return values.
Class docblock in crumbs_UI_Table
improve docs in crumbs_UI_Table
Fix #2313845: Use dirname(__FILE__) instead of __DIR__ for PHP 5.2 compatibility.
Fix #2316873. Illegal offset type in crumbs.views.inc.

views_page() can have an array as the second argument.
Add devel debug functionality.
minor docblock
Sanity checks and clarification for iterator use in PluginEngine.