Move lookup and link to partials (#106)

_includes/partial/publisher_link.html

@@ -0,0 +1,3 @@
+{% assign pub_small = include.pub | downcase %}
+{% assign publisher_ref = site.publishers | where: 'short_name', pub_small | first %}
+<a href="{{ publisher_ref.url | relative_url }}">{{ publisher_ref.name }}</a>

_layouts/collection/collection_base.html

@@ -15,10 +15,7 @@ layout: default
     <h1>{{ page.title }}</h1>
     <p>
       {{ page.date | date_to_string }}
-      {% assign publisher = site.publishers | where: 'short_name', page.author | first %}
+      {% include partial/publisher_link.html pub= page.author %}
-      {% if publisher %}
-        - <a href="{{ publisher.url | relative_url }}">{{ publisher.name }}</a>
-      {% endif %}
     </p>
     {{ content }}
 </article>

_layouts/collection/collection_index.html

@@ -14,7 +14,7 @@ layout: default
             <a href="{{ item.url | relative_url }}">{{ item.title }}</a>
           </h2>
           <span class="leading-relaxed mb-4">{{ item.excerpt | strip_html | strip_newlines | truncate: 156  }}</span>
-          <span>{{ item.date | date_to_string }} | {{ item.author }}</span>
+          <span>{{ item.date | date_to_string }} | {% include partial/publisher_link.html pub=item.author %}</span>
         </div>
       {% endfor %}
       </div>