Support passing html attributes into MenuItem
pass explorer-menu-url as a data attribute on the explorer menu link, so that we don't have to define it as a global in admin_base.html
Add register_admin_menu_item hook for registering MenuItems globally
Add an is_shown() method to allow globally-registered menu items to specify whether or not they should be shown on a given request
Convert all remaining menu items to be globally-registered with an is_shown method
Allow menu items to define their own javascript includes, and put the explorer menu js there rather than in core.js
documentation for register_admin_menu_item
Replace the MenuItem.render_js mechanism with the 'media' mechanism from django.forms, which does basically the same thing but better (e.g. handles de-duping where multiple items import the same js file)
add test for MenuItem media being included
Changed versionadded for RoutablePageMixin to 0.6
Fixes to RoutablePageMixin examples
Detail about image renditions and abstractimage fields
add tests for accessing advert_placements on a subclass of Page - these require modelcluster 0.4 to pass
upgrade modelcluster to 0.4 - fixes #545
Merge branch 'master' of github.com:torchbox/wagtail
Test the register_admin_menu_item hook, including the use of classnames/attrs and is_shown
Fix Page.copy() to copy child objects that are defined on a superclass of the model
Merge pull request #535 from gasman/feature/menu-api

Refactor admin menu API to allow menu items to have bundled JS
Changelog and release notes for #535
Added note to 0.6 saying that all features deprecated in 0.4 have been removed