Convert docdock theme from submodule to native files and fix Hugo compatibility

themes/docdock/layouts/partials/flex/scripts.html

@@ -0,0 +1,18 @@
+<script src="{{"js/jquery-2.x.min.js" | relURL}}"></script>
+<script type="text/javascript">
+    {{if .Site.IsMultiLingual}}
+        var baseurl = "{{.Site.BaseURL}}{{.Site.LanguagePrefix}}";
+    {{else}}
+        var baseurl = "{{.Site.BaseURL}}";
+    {{end}}
+</script>
+<script src="{{"js/clipboard.min.js" | relURL}}"></script>
+<script src="{{"js/featherlight.min.js" | relURL}}"></script>
+{{if eq .Site.Params.highlightClientSide true}}
+<script src="{{"js/highlight.pack.js" | relURL}}"></script>
+<script>hljs.initHighlightingOnLoad();</script>
+{{end}}
+<script type="text/javascript" src="{{"js/lunr.min.js" | relURL}}"></script>
+<script type="text/javascript" src="{{"js/auto-complete.js" | relURL}}"></script>
+<script type="text/javascript" src="{{"js/search.js" | relURL}}"></script>
+<script src="{{(printf "theme-%s/script.js" (.Site.Params.themeStyle| default "flex")) | relURL}}"></script>