Add first implementation of loading modal

app/templates/corpora/corpus_analysis.html.j2

@@ -3,6 +3,9 @@
 {% block page_content %}
 <script>
 socket.emit('init_corpus_analysis', {{ corpus_id }});
+socket.on('init_corpus_analysis', function(msg) {
+  if (msg === 'Ready') {M.Modal.getInstance(document.getElementById("loading-modal")).close();}
+});
 </script>
 
 
@@ -125,4 +128,23 @@ function sendQueryData() {
   console.log('Query data has been sent!')
 }
 </script>
+
+<div id="loading-modal" class="modal no-autoinit">
+  <div class="modal-content">
+    <h4>Waiting for analysis software</h4>
+    <div class="preloader-wrapper big active">
+      <div class="spinner-layer spinner-blue-only">
+        <div class="circle-clipper left">
+          <div class="circle"></div>
+        </div>
+        <div class="gap-patch">
+          <div class="circle"></div>
+        </div>
+        <div class="circle-clipper right">
+          <div class="circle"></div>
+        </div>
+      </div>
+    </div>
+  </div>
+</div>
 {% endblock %}