This subclass of Template Toolkit's Template::Parser parses multilingual
templates: templates that contain text in several languages.

    <t>
      <en>Hello!</en>
      <fr>Bonjour !</fr>
    </t>

Use this module directly if you have subclassed Template, otherwise you may
find it easier to use Template::Multilingual.

Language codes can be any string that matches \w+, but we suggest sticking
to ISO-639 which provides 2-letter codes for common languages and 3-letter
codes for many others.