Plone-app-theming

------------------

- Replace the stock "Themes" control panel with a renamed "Theming" control
panel, which incorporates the former's settings under its "Advanced" tab.
[optilude]

- Add a full in-Plone theme authoring environment
[optilude, vangheem]

- Update IBeforeTraverseEvent import to zope.traversing.
[hannosch]

- On tab "Manage themes", change table header to
better describe what's actually listed.
[kleist]

----------------

* Prevent AttributeError when getRequest returns None.
[maurits]

* Calculate subrequests against navigation root rather than portal.
[elro]

* Supply closest context found for 404 pages.
[elro]

* Lookup portal state with correct context.
[elro]

------------------

* Patch App.Management.Navigation to disable theming of ZMI pages.
[elro]

------------------

* Evaluate theme parameters regardless of whether there is a valid context or
not (e.g. when templating a 404 page).
[lentinj]

------------------

* Moved the *views* and *overrides* plugins out into a separate package
``plone.app.themingplugins``. If you want to use those features, you need
to install that package in your buildout. Themes attempting to register
views or overrides in environments where ``plone.app.themingplugins`` is not
installed will install, but views and overrides will not take effect.
[optilude]

------------------

* Support for setting arbitrary Doctypes.
[elro]

* Upgrade step to update plone.app.registry configuration.
[elro]

* Fixed plugin initialization when applying a theme.
[maurits]

* Query the resource directory using the 'currentTheme' name instead
of the Theme object (updating the control panel was broken).
[maurits]

* Fix zip import (plugin initialization was broken.)
[elro]