feature #5655 Added doc about Homestead's Symfony integration (WouterJ)

This PR was submitted for the 2.8 branch but it was merged into the 2.3 branch instead (closes #5655).

Discussion
----------

Added doc about Homestead's Symfony integration

| Q | A
| --- | ---
| Doc fix? | no
| New docs? | yes
| Applies to | all
| Fixed tickets | -

Commits
-------

d1d4275 Added doc about Homestead's Symfony integration

cookbook/map.rst.inc

@@ -245,3 +245,4 @@
 
   * :doc:`/cookbook/workflow/new_project_git`
   * :doc:`/cookbook/workflow/new_project_svn`
+  * :doc:`/cookbook/workflow/homestead`

cookbook/workflow/homestead.rst

@@ -0,0 +1,76 @@
+.. index:: Vagrant, Homestead
+
+Using Symfony with Homestead/Vagrant
+====================================
+
+In order to develop a Symfony application, you might want to use a virtual
+development environment instead of the built-in server or WAMP/LAMP. Homestead_
+is an easy-to-use Vagrant_ box to get a virtual environment up and running
+quickly.
+
+.. tip::
+
+    Due to the amount of filesystem operations in Symfony (e.g. updating cache
+    files and writing to log files), Symfony can slow down signifcantly. To
+    improve the speed, consider :ref:`overriding the cache and log directories <override-cache-dir>`
+    to a location outside the NFS share (for instance, by using
+    :phpfunction:`sys_get_temp_dir`). You can read `this blog post`_ for more
+    tips to speed up Symfony on Vagrant.
+
+Install Vagrant and Homestead
+-----------------------------
+
+Before you can use Homestead, you need to install and configure Vagrant and
+Homestead as explained in `the Homestead documentation`_.
+
+Setting Up a Symfony Application
+--------------------------------
+
+Imagine you've installed your Symfony application in
+``~/projects/symfony_demo`` on your local system. You first need Homestead to
+sync your files in this project. Execute ``homestead edit`` to edit the
+Homestead configuration and configure the ``~/projects`` directory:
+
+.. code-block:: yaml
+
+    # ...
+    folders:
+        - map: ~/projects
+          to: /home/vagrant/projects
+
+The ``projects/`` directory on your PC is now accessible at
+``/home/vagrant/projects`` in the Homestead environment.
+
+After you've done this, configure the Symfony application in the Homestead
+configuration:
+
+.. code-block:: yaml
+
+    # ...
+    sites:
+        - map: symfony-demo.dev
+          to: /home/vagrant/projects/symfony_demo/web
+          type: symfony
+
+The ``type`` option tells Homestead to use the Symfony nginx configuration.
+
+At last, edit the hosts file on your local machine to map ``symfony-demo.dev``
+to ``192.168.10.10`` (which is the IP used by Homestead)::
+
+    # /etc/hosts (unix) or C:\Windows\System32\drivers\etc\hosts (Windows)
+    192.168.10.10 symfony-demo.dev
+
+Now, navigate to ``http://symfony-demo.dev`` in your web browser and enjoy
+developing your Symfony application!
+
+.. seealso::
+
+    To learn more features of Homestead, including Blackfire Profiler
+    integration, automatic creation of MySQL databases and more, read the
+    `Daily Usage`_ section of the Homestead documentation.
+
+.. _Homestead: http://laravel.com/docs/homestead
+.. _Vagrant: https://www.vagrantup.com/
+.. _the Homestead documentation: http://laravel.com/docs/homestead#installation-and-setup
+.. _Daily Usage: http://laravel.com/docs/5.1/homestead#daily-usage
+.. _this blog post: http://www.whitewashing.de/2013/08/19/speedup_symfony2_on_vagrant_boxes.html

cookbook/workflow/index.rst

@@ -6,3 +6,4 @@ Workflow
 
     new_project_git
     new_project_svn
+    homestead