docs: add "Things about PHP" slides

things-to-know-php/sections/code-reuse.rst

@@ -0,0 +1,86 @@
+.. page:: titlePage
+
+.. class:: centredTitle
+
+Code reuse and collaboration
+
+.. page:: standardPage
+
+.. image:: images/projects-using-symfony.png
+   :width: 23cm
+
+.. page::
+
+.. image:: images/composer-logo.png
+   :height: 10cm
+
+.. page::
+
+.. image:: images/packagist-website.png
+
+.. page::
+
+.. image:: images/packagist-symfony-console.png
+
+.. page:: titlePage
+
+.. class:: centredtitle
+
+``composer require
+symfony/console``
+
+.. page::
+
+.. code-block:: json
+
+   {
+       "require": {
+            "symfony/console": "^4.2"
+       }
+   }
+
+
+.. page:: standardPage
+
+.. code-block:: php
+   :linenos:
+
+   <?php
+
+   require 'vendor/autoload.php';
+
+.. page::
+
+.. code-block:: php
+   :linenos:
+
+   <?php
+
+   require 'vendor/autoload.php';
+
+   $app = new \Symfony\Component\Console\Application();
+   $app->run();
+
+.. page::
+
+.. code-block:: php
+   :linenos:
+
+   <?php
+
+   require 'vendor/autoload.php';
+
+   use Symfony\Component\Console\Application;
+
+   $app = new Application();
+   $app->run();
+
+.. page:: imagePage
+
+.. image:: images/symfony-components.png
+    :width: 23cm
+
+.. page::
+
+.. image:: images/php-fig-website.png
+    :width: 23cm