tpl/tplimpl: Update RSS template

- Use publication date for pubdate
- Include version in generator element

Closes #3918
Closes #11692

tpl/tplimpl/embedded/templates/_default/rss.xml

@@ -48,7 +48,7 @@
     <title>{{ if eq .Title .Site.Title }}{{ .Site.Title }}{{ else }}{{ with .Title }}{{ . }} on {{ end }}{{ .Site.Title }}{{ end }}</title>
     <link>{{ .Permalink }}</link>
     <description>Recent content {{ if ne .Title .Site.Title }}{{ with .Title }}in {{ . }} {{ end }}{{ end }}on {{ .Site.Title }}</description>
-    <generator>Hugo -- gohugo.io</generator>
+    <generator>Hugo {{ hugo.Version }}</generator>
     <language>{{ site.Language.LanguageCode }}</language>{{ with $authorEmail }}
     <managingEditor>{{.}}{{ with $authorName }} ({{ . }}){{ end }}</managingEditor>{{ end }}{{ with $authorEmail }}
     <webMaster>{{ . }}{{ with $authorName }} ({{ . }}){{ end }}</webMaster>{{ end }}{{ with .Site.Copyright }}
@@ -61,7 +61,7 @@
     <item>
       <title>{{ .Title }}</title>
       <link>{{ .Permalink }}</link>
-      <pubDate>{{ .Date.Format "Mon, 02 Jan 2006 15:04:05 -0700" | safeHTML }}</pubDate>
+      <pubDate>{{ .PublishDate.Format "Mon, 02 Jan 2006 15:04:05 -0700" | safeHTML }}</pubDate>
       {{- with $authorEmail }}<author>{{ . }}{{ with $authorName }} ({{ . }}){{ end }}</author>{{ end }}
       <guid>{{ .Permalink }}</guid>
       <description>{{ .Summary | transform.XMLEscape | safeHTML }}</description>