minor #7523 Twig Extension does no longer need getName() method (mpdude, javiereguiluz)

This PR was submitted for the master branch but it was merged into the 2.7 branch instead (closes #7523).

Discussion
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Twig Extension does no longer need getName() method

This has been deprecated as of Twig 1.26, see https://github.com/twigphp/Twig/blob/v1.26.0/CHANGELOG#L7

Commits
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f94fd8f Fixed a syntax issue
200683e Minor change
c59a8d5 Fix .rst formatting
00f36bb Twig Extension does no longer need getName() method

Author: xabbuh

templating/twig_extension.rst

@@ -49,13 +49,16 @@ As an example you'll create a price filter to format a given number into price::
 
             return $price;
         }
-
-        public function getName()
-        {
-            return 'app_extension';
-        }
     }
 
+.. note::
+ 
+    Prior to Twig 1.26, your extension had to define an additional ``getName()``
+    method that returned a string with the extension's internal name (e.g.
+    ``app.my_extension``). When your extension needs to be compatible with Twig
+    versions before 1.26, include this method which is omitted in the example 
+    above.
+    
 .. tip::
 
     Along with custom filters, you can also add custom `functions`_ and register