Fix duplicate about nav link naming for tags

exampleSite/config.toml

@@ -48,6 +48,7 @@ hasCJKLanguage = true
 	about = ""
 	archive = ""
 	subscribe = ""
+	tags = ""
 	# Pagination links
 	olderPosts = ""
 	newerPosts = ""

layouts/partials/nav.html

@@ -4,7 +4,7 @@
 		<a href='{{ .Site.BaseURL }}'> <span class="arrow">←</span>{{ with .Site.Params.home }}{{ . }}{{ else }}Home{{ end }}</a>
 	{{ end }}
 	<a href='{{ .Site.BaseURL }}post'>{{ with .Site.Params.archive }}{{ . }}{{ else }}Archive{{ end }}</a>
-	<a href='{{ .Site.BaseURL }}tags'>{{ with .Site.Params.about }}{{ . }}{{ else }}Tags{{ end }}</a>
+	<a href='{{ .Site.BaseURL }}tags'>{{ with .Site.Params.tags }}{{ . }}{{ else }}Tags{{ end }}</a>
 	<a href='{{ .Site.BaseURL }}about'>{{ with .Site.Params.about }}{{ . }}{{ else }}About{{ end }}</a>
 
 	{{ range $key, $val := .Site.Params.Links }}