Includes:
* update checker refactored to \core\update\ namespace
* plugininfo classes refactored to \core\plugininfo\ namespace
* plugin_manager renamed to core_plugin_manager
* redirect back to original page after plugin uninstall
* fixed assign subplugin uninstall
* move assign subplugins under the assignment in admin tree
* fixed plugininfo for all question related plugin types
* auth uninstall support
* added missing block dependencies
* added theme uninstall
* subplugin types are following the plugin on plugin overview page
* several performance improvements in plugin manager
* new warnigns when plugininfo are outdated or missing
* multiple fixes and other improvements
This has been introduced in 2.5, so when upgrading from previous versions
make sure we set a default value. Otherwise, we get a notice about it
being undefined when we try to use it (and we always try to use it!).
They now share most of the code again, this time via subclassing, and they
share some code with enrol/ldap. They have also gained some features and a few
fixes.
Eloy Lafuente (stronk7)