Added footer template for docs with copyright

docs/docfx.json

@@ -50,6 +50,6 @@
       "_appTitle": "Perspex Website"
     },
     "dest": "_site",
-    "template": "default"
+    "template": [ "default", "template"]
   }
 }

docs/template/partials/footer.tmpl.partial

@@ -0,0 +1,13 @@
+{{!Copyright (c) Microsoft. All rights reserved. Licensed under the MIT license. See LICENSE file in the project root for full license information.}}
+
+<footer>
+  <div class="grad-bottom"></div>
+  <div class="footer">
+    <div class="container">
+      <span class="pull-right">
+        <a href="#top">Back to top</a>
+      </span>
+      <span>Copyright © 2016 The Perspex Project<br>Generated by <strong>DocFX</strong></span>
+    </div>
+  </div>
+</footer>