Currently rendering of the module menu of the backend left side is
quite complex. This is because there are several parts introduced
in recent TYPO3 versions, that have only substituted parts of the
existing code. So the "old" code was still in use. To give a better
understanding I will first introduce all the parts relevant to the
rendering of the module menu.

PHP side
 * The mother of all classes is ModuleLoader.php, originally made by
   Kasper, which takes TBE_MODULES and compiles a long list of all
   modules into an array. (ModuleLoader->load()). Currently this class
   is kept as is for the time being.
 * For 4.1/4.2, the ModuleMenuView was introduced, a wrapper class to
   access the data of ModuleLoader and also does some other stuff like
   saving the Open/Collapsed state of the modules via AJAX (note: this
   will be handled browser-internally via LocalStorage from now on, as
   it saves HTTP requests).
   It does one other thing: Rendering of the Logout Button.
   This is completely in the wrong place right now, as the Logout
   button isn't within the module menu frame anymore since 4.x,
   but on the top right area of the backend.
 * The BackendController class is responsible for adding all HTML and
   JS code code to the backend.php page so it can be rendered. It
   instantiates the ModuleMenuView class to call the LogoutButton
   function.
 * As one of the first steps of rewriting the module menu a couple of
   versions ago, there was a ModuleController, which was again a
   wrapper for ModuleLoader while putting everything together in a
   ModuleRepository, along with Module objects and a singleton object
   ModuleStorage. This new version allows for nesting of up to three
   levels (incl. modfuncs), along with clear objects instead of arrays.

JS side
 * The module menu isn't output with a single line of PHP code, as it
   is defined as a ExtJS storage which fetches the module menu
   asynchronously. The HTML code is built in a ExtJS template, which
   leads to the funny effect that the raw backend.php only zero HTML
   code output for the module menu.
   An extra AJAX request is fired to load up the module, which then is
   prepared and templated by ExtJS.

The changes:
 * The logout button rendering is now done in the BackendController
   and not in the ModuleMenuView class.
 * The menu is now outputted in the BackendController at the same
   time as backend.php by a standalone Fluid template. The menu is
   built by a simple call to the ModuleRepository which returns a
   ModuleStorage.
 * ModuleMenuView, ModuleMenuController are not needed anymore, and
   are deprecated.
 * The JS is rewritten so that it works as before. These parts are filled
   up with jQuery code.
 * The collapsed/open state of the main modules is now done via the
   local storage JS functionality of the browsers to avoid further
   unnecessary HTTP loading operations.

Resolves: #60633
Releases: 6.3
Change-Id: I5402c1345a2931340d7ec9ef1881877b39d1bfc3
Reviewed-on: http://review.typo3.org/31876


Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Reviewed-by: Benjamin Mack <benni@typo3.org>
Tested-by: Benjamin Mack <benni@typo3.org>