Update footer email link to stackable.tech (#48)

Author: nightkr

template/_footer.html

@@ -41,7 +41,7 @@ <h2>Support</h2>
           <h2>Get in touch</h2>
           <ul class="footer-link-list">
             <li>
-              <a href="mailto:info@stackable.de">info@stackable.de</a>
+              <a href="mailto:info@stackable.tech">info@stackable.tech</a>
             </li>
             <li>
               <a href="tel:+4941039263100">+49 4103 926 3100</a>