Correct like to evolution.md

Author: abh3

_layouts/default.html

@@ -31,7 +31,7 @@
     <li><a href="{{ '/development.html' | relative_url }}"
         {% if page.tab == "development" %} class="active" {% endif %}>
         development</a></li>
-    <li><a href={{ '/evolution.html' | relative_url }}"
+    <li><a href="{{ '/evolution.html' | relative_url }}"
         {% if page.tab == "evolution" %} class="active" {% endif %}>
         evolution</a></li>
     <li><a href="{{ '/collaboration.html' | relative_url }}"