minor #58 The no-brainer topic merges/removal (WouterJ)

This PR was squashed before being merged into the 2.7 branch (closes #58).

Discussion
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The no-brainer topic merges/removal

This is just a rebase of #44.

Commits
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8320bad The no-brainer topic merges/removal

Author: javiereguiluz

upgrade/_update_all_packages.rst.inc renamed to install/_update_all_packages.rst.inc

@@ -1,8 +1,5 @@
-.. index::
-    single: Upgrading
-
-Upgrading
-=========
+Install and Upgrade
+===================
 
 So a new Symfony release has come out and you want to upgrade, great! Fortunately,
 because Symfony protects backwards-compatibility very closely, this *should*
@@ -13,7 +10,7 @@ There are three types of upgrades, all needing a little different preparation:
 .. toctree::
     :maxdepth: 2
 
-    /upgrade/patch_version
-    /upgrade/minor_version
-    /upgrade/major_version
-    /upgrade/bundles
+    /cookbook/upgrade/patch_version
+    /cookbook/upgrade/minor_version
+    /cookbook/upgrade/major_version
+    /cookbook/upgrade/bundles

upgrade/_update_dep_errors.rst.inc renamed to install/_update_dep_errors.rst.inc

@@ -64,7 +64,8 @@ On the other hand, the bridge provide a factory interface called
 :class:`Symfony\\Bridge\\PsrHttpMessage\\HttpFoundationFactoryInterface`
 that builds HttpFoundation objects from objects implementing PSR-7 interfaces.
 
-The next snippet explain how to convert an object implementing the :class:`Psr\\Http\\Message\\ServerRequestInterface`
+The next snippet explain how to convert an object implementing the
+:class:`Psr\\Http\\Message\\ServerRequestInterface`
 interface to a :class:`Symfony\\Component\\HttpFoundation\\Request` instance::
 
     use Symfony\Bridge\PsrHttpMessage\Factory\HttpFoundationFactory;