call: group call design: Design for group call (which is used for both group call and A/V conferences) has been improved to: - have a working fullscreen button; - have a better display of peer users in grid, with responsive design; - have a nicer design for peer user, and adding avatar/nickname as overlay on the bottom of the video stream; - add a way to (un)pin a peer user, which make is appear on the whole width on top of the grid. rel 448 HG<S-Insert>: changed sat_templates/templates/bulma/call/group_peer.html

{% macro form(action='', class=none, id=none, method="post", use_csrf_token=true) %}
    <form method="{{method}}" action="{{action}}" {{ {'id': id, 'class': class}|xmlattr }} {{kwargs|xmlattr}} >
        {% if csrf_token is defined and use_csrf_token %}
            <input type="hidden" name="csrf_token" value="{{csrf_token}}">
        {% endif %}
        {{ caller() }}
    </form>
{% endmacro %}