feat: render keywords for each article

templates/archives.html

@@ -1,6 +1,7 @@
 {% extends "base.html" %}
 
 {% block title %}{{ article.article.title }}{% endblock title %}
+{% block keywords %}{{ article.article.keywords| join(sep=", ") }}{% endblock keywords %}
 {% block body %}
 
 <section class="full-page">

templates/base.html

@@ -4,6 +4,7 @@
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <meta http-equiv="X-UA-Compatible" content="ie=edge">
+    <meta name="keywords" content="{% block keywords %}{% endblock keywords %}" />
     <link rel="stylesheet" href="/statics/style.css">
     <title>{% block title %}Rubble{% endblock title %}</title>
 </head>