Add status flag for not translated message

weblate/html/unit-state.html

 {% load i18n %}
 <td>
 {% if item.fuzzy %}<span title="{% trans "Message is fuzzy" %}" class="flag-icon ui-icon ui-icon-help"></span>{% else %}
+{% if not item.translated %}<span title="{% trans "Message is not translated" %}" class="flag-icon ui-icon ui-icon-document-b"></span>{% else %}
 {% if item.has_failing_check %}<span title="{% trans "Message has failing checks" %}" class="flag-icon ui-icon ui-icon-notice"></span>{% else %}
 {% if item.translated %}<span title="{% trans "Message is translated" %}" class="flag-icon ui-icon ui-icon-check"></span>{% endif %}
-{% endif %}{% endif %}
+{% endif %}{% endif %}{% endif %}
 {% if item.has_comment %}<span title="{% trans "Message has comments" %}" class="flag-icon ui-icon ui-icon-comment"></span>{% endif %}
 </td>