[docs] upgrade guide from 2.4 to 3.0

docs/upgrade/3.0.rst

@@ -13,6 +13,8 @@ What's new in 3.0
     3.0 introduces some changes that **require** action if you are upgrading
     from a previous version.
 
+.. note:: :ref:`Click here to see the quick upgrade guide <upgrading-from-2.4>`
+
 New Frontend Editing
 ====================
 
@@ -97,6 +99,8 @@ If you have ``django-reversion`` installed you now have **undo** and **redo**
 options available directly in the toolbar. These can now revert *plugin*
 content as well as *page* content.
 
+.. _ex-core-plugins:
+
 Plugins removed
 ===============
 
@@ -206,6 +210,7 @@ to keep your existing files from the old ``cms.plugins.snippet``!)
 
 * https://github.com/pbs/django-cms-smartsnippets
 
+.. _cmsplugin-twitter-removed:
 
 Twitter Plugin
 --------------
@@ -400,6 +405,54 @@ A new ``CMS_TEMPLATE`` variable is now available in the context: it contains the
 current page template.
 See :ref:`CMS_TEMPLATE reference <page_template>` for details.
 
+
+.. _upgrading-from-2.4:
+
+******************
+Upgrading from 2.4
+******************
+
+If you want to upgrade from version 2.4 to 3.0, there's a few things you need to do.
+Start of by updating the cms' package::
+
+    pip install django-cms==3.0
+
+
+Next, you need to make the following changes in your ``settings.py``
+
+* settings.INSTALLED_APPS
+
+    * Remove ``cms.plugin.twitter``. This package has been deprecated, see :ref:`cmsplugin-twitter-removed`.
+    * Rename all the other ``cms.plugins.X`` to ``djangocms_X``, see :ref:`ex-core-plugins`.
+
+* settings.CONTEXT_PROCESSORS
+
+    * Replace ``cms.context_processors.media`` with ``cms.context_processors.cms_settings``
+
+Afterwards, install all your previously renamed ex-core plugins (djangocms-X). Here's a full list, but you probably
+don't need all of them::
+
+    pip install djangocms-file
+    pip install djangocms-flash
+    pip install djangocms-googlemap
+    pip install djangocms-inherit
+    pip install djangocms-picture
+    pip install djangocms-teaser
+    pip install djangocms-video
+    pip install djangocms-link
+    pip install djangocms-snippet
+
+
+Also, please check your templates to make sure that you haven't put the ``{% cms_toolbar %}`` tag into a ``{% block %}``
+tag. This is not allowed in 3.0 anymore.
+
+To finish up, please update your database::
+
+    python manage.py syncdb
+    python manage.py migrate  (answer yes if your prompted to delete stale content types)
+
+That's it!
+
 ********************
 Pending deprecations
 ********************