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

<div class="main_notification columns is-centered">
    <div class="column is-narrow has-items-centered">
        {% set level_map={
            'success': 'is-success',
            'info': 'is-info',
            'warning': 'is-warning',
            'error': 'is-danger'
            }
        %}

        <div class="notification {{level_map[level]}} pr-6 py-4">
            <button class="delete click_to_close"></button>
            {{message}}
        </div>
    </div>
</div>