Add license information

layouts/partials/powered-by.html

@@ -0,0 +1,14 @@
+{{ if ne .Site.Params.powered_by false }}
+  <p class="muted">
+    This page was generated by
+    <a href="https://gohugo.io/">Hugo</a>
+    using the
+    <a href="https://comfusion.github.io/after-dark/">After Dark</a>
+    theme by
+    <a href="http://comfusionllc.com">Comfusion</a>.
+    <br />
+    The content is relased unter the 
+    <a href="https://github.com/vbrandl/vbrandl.net/blob/master/LICENSE">CC-BY-SA-4.0</a>
+    license.
+  </p>
+{{ end }}