fix(clear button clears field): as suggested by @b-g

fix #92

Author: ff6347

_includes/search-bar.html

@@ -1,5 +1,5 @@
 <div id="flex-search">
-    <input class="searchfield flex-search-item" id="lunr-search" placeholder="Search" /> <button id="lunr-clear" class="flex-search-item">Clear</button>
+    <input class="searchfield flex-search-item" type="search" id="lunr-search" placeholder="Search" /> <button id="lunr-clear" class="flex-search-item">Clear</button>
 </div>
 <div class="flex-search-advanced-hints">
     <div id="advanced-search-hint">

assets/js/src/reference.js

@@ -80,7 +80,7 @@ document.addEventListener('DOMContentLoaded', function() {
 
     if (clearbutton !== null) {
       clearbutton.addEventListener('click', event => {
-
+        searchfield.value = '';
         if (searchresults !== null) {
           clearElement(searchresults);
         }