issue 4565 - add meta images

includes/jobs/header.tmpl

 {#
   For each job opening you have to list the title and the name of the file under
   pages/jobs that contains the job description.
 #}
 {% set openings = [
   ("Frontend Developer", "frontend-developer", 33),
   ("Software Tester", "software-tester", 147),
   ("Filter List Supporter", "filter-list-supporter", 127),
   ("Social Media Manager", "social-media-manager", 133),
   ("Student Help - Monitoring", "student-help", 110),
   ("Whitelist Maintainer", "whitelist-maintainer", 108),
   ("Speculative Application", "speculative-application", 51),
 ] %}
 
 {% set opening = openings|find(page.split("/")[-1], attribute=1) %}
 {% set title = (opening or [title])[0] %}
+{% set og_image = "images/eyeo-meta-jobs.png" %}
 
 <header class="page-title">
   <h1>Working at Eyeo</h1>
 </header>
 
 <div id="jobs-info" class="content-block">
   <div id="tabs-openings" class="columns-container one-sidebar">
     <div class="column sidebar-left">
       <h3 class="heading centered"><span>Current openings:</span></h3>
 
@@ skipping 19 matching lines @@
         <img id="ihk-logo" src="/images/ihk.png" alt="IHK Ausbildungsbetrieb" width="120" height="80">
         <img id="fair-company-logo" src="/images/fair-company.jpg" alt="Fair Company" height="80">
       </p>
     </div>
 
     <div class="column">
       <div id="panels-openings" class="ui-tabs-panel">
         {% if opening %}
         <h2>{{ title }}</h2>
         {% endif %}