Merge branch '6.0' into 6.1

* 6.0:
  [Contributing] Mention `php-symfony` and `php-standalone` markup formats

Author: javiereguiluz

contributing/documentation/format.rst

@@ -90,11 +90,26 @@ The previous reStructuredText snippet renders as follow:
 
         // Configuration in PHP
 
+All code examples assume that you are using that feature inside a Symfony
+application. If you ever need to also show how to use it when working with
+standalone components in any PHP application, use the special formats
+``php-symfony`` and ``php-standalone``, which will be rendered like this:
+
+.. configuration-block::
+
+    .. code-block:: php-symfony
+
+        // PHP code using features provided by the Symfony framework
+
+    .. code-block:: php-standalone
+
+        // PHP code using standalone components
+
 The current list of supported formats are the following:
 
-===================  ======================================
+===================  ==============================================================================
 Markup Format        Use It to Display
-===================  ======================================
+===================  ==============================================================================
 ``html``             HTML
 ``xml``              XML
 ``php``              PHP
@@ -105,7 +120,9 @@ Markup Format        Use It to Display
 ``ini``              INI
 ``php-annotations``  PHP Annotations
 ``php-attributes``   PHP Attributes
-===================  ======================================
+``php-symfony``      PHP code example when using the Symfony framework
+``php-standalone``   PHP code to be used in any PHP application using standalone Symfony components
+===================  ==============================================================================
 
 Adding Links
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