merged branch MyKiwi/improving_render_html (PR #691)

This PR was merged into the master branch.

Discussion
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[Doc] Add code-block for remove the red prompt

Commits
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18159ea1 Add code-block for remove the red prompt

doc/usage.rst

@@ -46,7 +46,9 @@ Upgrading
 ---------
 
 Upgrading Silex to the latest version is as easy as running the ``update``
-command::
+command:
+
+.. code-block:: bash
 
     $ php composer.phar update