Table filters

* adds table filtering for InterventionTable
* adds default ordering
* moves user-access filtering from view to InterventionTableFiler
* adds generic render_icn method for BaseTable (for usage with fontawesome5)
* adds translations
* improves table.html template

templates/table.html

@@ -26,9 +26,9 @@
         {% endcomment %}
         <div class="row my-1">
             <div class="col-sm-12 col-md-8 col-lg-6">
-                <form method="get" action="{{table.filter}}">
+                <form method="get">
                     <div class="input-group">
-                        <input type="text" class="form-control" aria-label="{% trans 'Search for keywords' %}" placeholder="{% trans 'Search' %}">
+                        <input id="id_q" name="q" type="text" class="form-control" aria-label="{% trans 'Search for keywords' %}" placeholder="{% trans 'Search' %}" value="{{ request.GET.q }}">
                         <div class="input-group-append" title="{% trans 'Start search' %}">
                             <button type="submit" class="btn btn-default input-group-text">
                                 <span class="">
@@ -72,6 +72,10 @@
                         <div class="card-body">
                             <form method="get">
                                 {{ table.filter.form.as_p }}
+                                <button class="btn btn-default" title="{% trans 'Filter' %}">
+                                    {% fa5_icon 'filter' %}
+                                    {% trans 'Apply filter' %}
+                                </button>
                             </form>
                         </div>
                     </div>