added remove all item from queue

src/server/web/templates/queue.html

@@ -124,6 +124,10 @@
                         Download Queue (<span id="queue-count">0</span>)
                     </h2>
                     <div class="section-actions">
+                        <button id="clear-pending-btn" class="btn btn-secondary" disabled>
+                            <i class="fas fa-trash-alt"></i>
+                            Remove All
+                        </button>
                         <button id="start-queue-btn" class="btn btn-primary" disabled>
                             <i class="fas fa-play"></i>
                             Start