Update to Hugo 0.53 and remove all .Site references (#12079)

* Remove all .Site variable references

* Update Hugo version in Travis CI config and Makefile

layouts/shortcodes/codenew.html

@@ -4,7 +4,7 @@
 {{ $fileDir := path.Split $file }}
 {{ $bundlePath := path.Join .Page.Dir $fileDir.Dir }}
 {{ $filename := printf "/content/%s/examples/%s" .Page.Lang $file | safeURL }}
-{{ $ghlink := printf "https://%s/master%s" .Page.Site.Params.githubWebsiteRaw $filename | safeURL }}
+{{ $ghlink := printf "https://%s/master%s" site.Params.githubWebsiteRaw $filename | safeURL }}
 {{/* First assume this is a bundle and the file is inside it. */}}
 {{ $resource := $p.Resources.GetMatch (printf "%s*" $file ) }}
 {{ with $resource }}
@@ -15,7 +15,7 @@
 {{ with $resource }}{{ $.Scratch.Set "content" . }}{{ end }}
 {{ end }}
 {{ if not ($.Scratch.Get "content") }}
-{{ errorf "[%s] %q not found in %q" $p.Site.Language.Lang $fileDir.File $bundlePath }}
+{{ errorf "[%s] %q not found in %q" site.Language.Lang $fileDir.File $bundlePath }}
 {{ end }}
 {{ with $.Scratch.Get "content" }}
 <table class="includecode" id="{{ $file | anchorize }}">