Draft: Overall Motivation

Overview on the high-level purpose of HIFIS.

So far it's basically a collection of "Hifis-for-you" and "Mission" text stubs

Closes #126 (closed)

_includes/frontpage/title-content.html

 <div>
     <h1>Federated IT for Science</h1>
-    <p>HIFIS ensures an excellent information environment for outstanding research in all Helmholtz research fields.</p>
+    <p>HIFIS ensures an excellent information environment for outstanding research in all Helmholtz research fields.
+    <a href="{{ '/motivation' | relative_url }}" class="btn btn-success">Find out more on the aims of HIFIS</a>
+    </p>
 </div>
 <div class="services-box">
     <div class="services-title-buttons">