Add documentation search to the site

Signed-off-by: jonasrosland <jrosland@vmware.com>

site/_includes/head-docs.html

@@ -5,5 +5,6 @@
   <link rel="shortcut icon" href="/favicon.ico" type="image/x-icon">
   <link rel="icon" href="/favicon.ico" type="image/x-icon">
   <link rel="stylesheet" href="/css/styles.css?{{site.time | date: '%s%N'}}">
+  <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/docsearch.js@2/dist/cdn/docsearch.min.css" />
   {% seo %}
 </head>

site/_layouts/docs.html

@@ -27,8 +27,14 @@
           <div class="container container-max">
             <div class="row">
               <div class="col-md-3 toc">
-              {% include versions.html %}
-              {% include nav.html %}
+                {% include versions.html %}
+                <br />
+                <form class="d-flex align-items-center">
+                  <span class="algolia-autocomplete" style="position: relative; display: inline-block; direction: ltr;">
+                    <input type="search" class="form-control docsearch-input" id="search-input" placeholder="Search..." aria-label="Search for..." autocomplete="off" spellcheck="false" role="combobox" aria-autocomplete="list" aria-expanded="false" aria-owns="algolia-autocomplete-listbox-0" dir="auto" style="position: relative; vertical-align: top;">
+                  </span>
+                </form>
+                {% include nav.html %}
               </div>
               <div class="col-md-8">
               {% include version-warning.html %}
@@ -42,6 +48,15 @@
       {% include footer.html %}
     </div>
   </div>
+<script type="text/javascript" src="https://cdn.jsdelivr.net/npm/docsearch.js@2/dist/cdn/docsearch.min.js"></script>
+<script type="text/javascript"> docsearch({
+apiKey: '3d80f66bb5ecf85f8e2760caef383f24',
+indexName: 'velero',
+inputSelector: '.docsearch-input',
+algoliaOptions: { 'facetFilters': ["version:{{ page.version }}"] },
+debug: false // Set debug to true if you want to inspect the dropdown
+});
+</script>
 </body>
 
 </html>