Provide the missing examples from the "Built-in template tags and filters" page

[Daniel Greenfeld]

Any template tag or filter that doesn't reference another page should have at least one example. Missing examples include:

• comment
• debug
• ifnotequal (is this one necessary?)
• templatetag
• dictsortreversed (is this one necessary?)
• escape
• force_escape
• pprint
• timesince
• timeuntil

[Daniel Greenfeld]

The following won't be included in my patch:

• debug is such a special case I'm not including it in this ticket anymore.
• ifnotequal should not be documented, just so that people are encouraged more to use the '!=' and 'is not' operators.
• dictsortreversed is not being covered as the story is too simple to require an example.
• As pprint is supposed to "Prints the formatted representation of object on stream, followed by a newline" and doesn't seem to actually do that when I try it, I suspect this filter is broken. May open a separate ticket on it.

[Julien Phalip]

Great idea! Please do open a ticket for pprint if you find an issue with it. Thanks!

[Daniel Greenfeld]

Pull request submitted! See ​https://github.com/django/django/pull/509

[Daniel Greenfeld]

Just confirmed that pprint does work but it's hard to come up with a good, terse example. Leaving it off for the same reason I'm leaving off debug. It's too special of a case.

[Aymeric Augustin]

The pull request looks good, I've left only a small comment.

[Aymeric Augustin <aymeric.augustin@…>]

In e27a43cc54f120c49cac33b36568b128bcfaef5a:

Merge pull request #509 from pydanny/ticket_19244

Fixed #19244 -- Provided examples for some built-in templatetags and filters