base: implemented language button: - `component.menu` can now be used with a `{% call %}`, allowing extra HTML to be added after in the <nav> element - a language dropdown is shown if more than one translation is available, allowing to change page locale - if javascript is available, only the dropdown is visible, and changing it reload the page with new locale - if javascript is not available, a submit button is display to change the locale

{# creata a new ticket #}

{% set category_menu = [('merge-requests', url_tickets_list)] %}
{% extends 'base/base.html' %}
{% block body %}
<div class="box message--info">
    <p>{% trans %}It is not yet possible to create a merge request from inside Libervia, please use <pre>jp merge-request set</pre> for now. Merge requests welcome ;){% endtrans %}</p>
</div>
{% endblock body %}