Only show "No Description" to repo admins (#2167)

Only show note about missing description ("No Description") to repo admins, nobody else can change it.

templates/repo/home.tmpl

@@ -4,7 +4,7 @@
 	<div class="ui container">
 		{{template "base/alert" .}}
 		<p id="repo-desc">
-			{{if .Repository.DescriptionHTML}}<span class="description has-emoji">{{.Repository.DescriptionHTML}}</span>{{else}}<span class="no-description text-italic">{{.i18n.Tr "repo.no_desc"}}</span>{{end}}
+			{{if .Repository.DescriptionHTML}}<span class="description has-emoji">{{.Repository.DescriptionHTML}}</span>{{else if .IsRepositoryAdmin}}<span class="no-description text-italic">{{.i18n.Tr "repo.no_desc"}}</span>{{end}}
 			<a class="link" href="{{.Repository.Website}}">{{.Repository.Website}}</a>
 		</p>
 		<div class="ui secondary menu">