Add files via upload

js/include.js

@@ -0,0 +1,19 @@
+function includeHTML() {
+    var elements = document.getElementsByTagName("include");
+    for (var i = 0; i < elements.length; i++) {
+      var element = elements[i];
+      var file = element.getAttribute("src");
+      if (file) {
+        var xhttp = new XMLHttpRequest();
+        xhttp.onreadystatechange = function() {
+          if (this.readyState === 4 && this.status === 200) {
+            element.innerHTML = this.responseText;
+          }
+        };
+        xhttp.open("GET", file, true);
+        xhttp.send();
+      }
+    }
+  }
+  
+  document.addEventListener("DOMContentLoaded", includeHTML);