Resolve "Learning materials"

Review here

Closes #276 (closed) #236 (closed)

_includes/cards/post_card.html

@@ -2,7 +2,8 @@
 
 This is a card displaying post title and date.
 Parameters:
-post: The post which sould be displayed on the card
+post: The post which sould be displayed on the card.
+exclude_date: Do not show the date on the image card.
 
 {%- endcomment -%}
 {%- if include.post.title_image == "default" %}
@@ -17,15 +18,20 @@ post: The post which sould be displayed on the card
     | strip 
     | relative_url -%}
 {%- endif -%}
+{%- if include.exclude_date | default: false -%}
+{%- assign justify-content-class = "justify-content-center" -%}
+{%- endif -%}
 <div class="card image-card bg-primary">
     <img src="{{ img_url }}" class="card-img" alt="Title image for {{ post.title }}">
-    <div class="card-img-overlay" style="padding-left: 0.5rem !important;padding-right: 0.5rem !important;">
+    <div class="card-img-overlay {{ justify-content-class }}" style="padding-left: 0.5rem !important;padding-right: 0.5rem !important;">
+        {%- unless include.exclude_date | default: false -%}
         <div class="card-title">
             <span class="badge badge-secondary">
                 <i class="fas fa-calendar-day" aria-hidden="true"></i>
                 {{ include.post.date | date: "%d.&thinsp;%b.&thinsp;%y" }}
             </span>
         </div>
+        {%- endunless -%}
         <div class="card-text" style="padding-left: 0.7rem !important;padding-right: 0.7rem !important;">
             <a href="{{ include.post.url | relative_url }}" class="stretched-link">
                 <h4>{{ include.post.title }}</h4>