Fixed #5591: corrected info about variables in `trans` tag. Thanks, idangazit.

tags and a slightly different syntax than in Python code. To give your template

access to these tags, put ``{% load i18n %}`` toward the top of your template.

The ``{% trans %}`` template tag translates a constant string or a variable

content::

The ``{% trans %}`` template tag translates either a constant string 

(enclosed in single or double quotes) or variable content::

    <title>{% trans "This is the title." %}</title>

    <title>{% trans myvar %}</title>

If you only want to mark a value for translation, but translate it later from a

variable, use the ``noop`` option::

If the ``noop`` option is present, variable lookup still takes place but the

translation is skipped. This is useful when "stubbing out" content that will

require translation in the future::

    <title>{% trans "value" noop %}</title>

    <title>{% trans "myvar" noop %}</title>

It's not possible to use template variables in ``{% trans %}`` -- only constant

strings, in single or double quotes, are allowed. If your translations require

variables (placeholders), use ``{% blocktrans %}``. Example::

It's not possible to mix a template variable inside a string within

``{% trans %}``. If your translations require strings with variables (placeholders),

use ``{% blocktrans %}``. Example::

    {% blocktrans %}This will have {{ value }} inside.{% endblocktrans %}

    {% blocktrans %}This string will have {{ value }} inside.{% endblocktrans %}

To translate a template expression -- say, using template filters -- you need

to bind the expression to a local variable for use within the translation