Allow multiple post authors

Author: maennchen

_layouts/post.html

@@ -11,7 +11,7 @@ <h1>{{ page.title }}</h1>
         {% if page.subtitle %}
         <h2>{{ page.subtitle }}</h2>
         {% endif %}
-        <div class="byline">{{ page.date | date: "%B %d, %Y" }}{% if page.author %} &middot; by {{ page.author}}{% endif %} &middot; in {% for category in page.categories %}
+        <div class="byline">{{ page.date | date: "%B %d, %Y" }}{% if page.author %} &middot; by {{ page.author }}{% endif %}{% if page.authors %} &middot; by {{ page.authors | join: ", " }}{% endif %} &middot; in {% for category in page.categories %}
           {% if category == "Elixir in Production" %}
             <a class="category" href="/cases.html">{{ category }}</a>
           {% else %}

atom.xml

@@ -16,10 +16,15 @@ elixir_url: http://elixir-lang.org
   <title>{{ post.title }}</title>
   <link href="{{ page.elixir_url }}{{ post.url }}"/>
   {% if post.author %}
-  <author>
-    <name>{{ post.author }}</name>
-  </author>
+    <author>
+      <name>{{ post.author }}</name>
+    </author>
   {% endif %}
+  {% for author in post.authors %}
+    <author>
+      <name>{{ author }}</name>
+    </author>
+  {% endfor %}
   <updated>{{ post.date | date_to_xmlschema }}</updated>
   <id>{{ post.id }}</id>
   <content type="html">{{ post.content | xml_escape }}</content>

blog/index.html

@@ -9,7 +9,7 @@
     <div class="hentry post">
       <div class="sticky-header">
         <h2 class="entry-title"><a class="spec" href="{{ post.url }}" title="{{ post.title }}" rel="bookmark">{{ post.title }}</a></h2>
-        <div class="byline">{{ post.date | date: "%B %d, %Y" }}{% if post.author %} · by {{ post.author}}{% endif %} . in {% for category in post.categories %}<a href="/blog/categories.html#{{category}}" class="category">{{ category }}</a>{% endfor %}</div>
+        <div class="byline">{{ post.date | date: "%B %d, %Y" }}{% if post.author %} · by {{ post.author }}{% endif %}{% if post.authors %} · by {{ post.authors | join: ", " }}{% endif %} . in {% for category in post.categories %}<a href="/blog/categories.html#{{category}}" class="category">{{ category }}</a>{% endfor %}</div>
       </div><!-- .sticky-header -->
 
       <div class="entry-summary">