Fix URL in documentation

Author: ESultanik

docs/_templates/layout.html

@@ -17,7 +17,7 @@
             {% endfor %}
           {% else %}
             <dd><a href="/graphtage/latest">latest</a></dd>
-            <dd><a href="/graphtage/v0.2.1">0.2.2</a></dd>
+            <dd><a href="/graphtage/v0.2.2">0.2.2</a></dd>
             <dd><a href="/graphtage/v0.2.1">0.2.1</a></dd>
             <dd><a href="/graphtage/v0.2.0">0.2.0</a></dd>
             <dd><a href="/graphtage/v0.1.1">0.1.1</a></dd>