Bing search for China users (#9845)

* Updates readme's site building instructions

* Alters dockerfile to use extended hugo build

This is necessary for the pipes used w/ TOCSS since node-sass was dropped

* WIP for bing search implementation

* Implements Bing search instead of google

* Makes bing the default result provider and uses google and it's available

* Adds pagination to bing and replaces the $.get call with a $.ajax call

* front adjust

* bing limit pagination

* Adds break if there are less than 10 pages worth of results on bing search

* Adds proper google script ref and proper config id

* Removes console.log call

layouts/docs/search.html

@@ -1,23 +1,12 @@
 {{ define "content" }}
 <h1>{{ .Title }}</h1>
-<script type="text/javascript">
-  document.write('<gcse:searchresults-only linktarget="_parent"></gcse:searchresults-only>');
-</script>
 
-<script>
-  (function() {
-    var cx = '013288817511911618469:elfqqbqldzg';
-    var gcse = document.createElement('script');
-    gcse.type = 'text/javascript';
-    gcse.async = true;
-    gcse.src = (document.location.protocol == 'https:' ? 'https:' : 'http:') +
-        '//cse.google.com/cse.js?cx=' + cx;
-    var s = document.getElementsByTagName('script')[0];
-    s.parentNode.insertBefore(gcse, s);
+<gcse:searchresults-only linktarget="_parent">
+    <div id="bing-results-container">Fetching results..</div>
+    <div id="bing-pagination-container"></div>
+</gcse:searchresults-only>
 
-    document.querySelector('html').classList.add('search');
-  })();
-</script>
+<script src="{{ "js/search.js" | relURL }}"></script>
 {{ end }}