Remove tojson filter in docs

docs/templating.rst

@@ -97,29 +97,6 @@ by default:
 
       {% from '_helpers.html' import my_macro with context %}
 
-Standard Filters
-----------------
-
-These filters are available in Jinja2 additionally to the filters provided
-by Jinja2 itself:
-
-.. function:: tojson
-   :noindex:
-
-   This function converts the given object into JSON representation.  This
-   is for example very helpful if you try to generate JavaScript on the
-   fly.
-
-   Note that inside ``script`` tags no escaping must take place, so make
-   sure to disable escaping with ``|safe`` before Flask 0.10 if you intend
-   to use it inside ``script`` tags:
-
-   .. sourcecode:: html+jinja
-
-       <script type=text/javascript>
-           doSomethingWith({{ user.username|tojson|safe }});
-       </script>
-
 Controlling Autoescaping
 ------------------------