Fix template variable for adding semantics to article

 $var breadcrumbs = breadcrumbs
 $var title: $:str(mkdn(title))[3:-4]
 $var title_classes = ["p-name"]
-$var classes = ["h-entry"]
+$var article_classes = ["h-entry"]
 
 <link rel=stylesheet href=$tx.origin/static/solarized.css media=screen>
 <style>

 $var breadcrumbs = ("projects", "Projects", project, (None, ["u-ragt.ag-change-of"], f"<b>{project}</b>"))
 $var title: Commit Log
 $var title_classes = ["p-name"]
-$var classes = ["h-feed"]
+$var article_classes = ["h-feed"]
 
 $for commit_id, commit in repo.log().items():
     $ title, _, description = commit["message"].partition("\n\n")

 $var breadcrumbs = ("projects", "Projects")
 $ title = project
 $var title_classes = ["p-name"]
-$var classes = ["h-ragt-ag-project"]
+$var article_classes = ["h-ragt-ag-project"]
 
 <style>
 /* h2 {