set version to 0.13.0pre

_layouts/default.html

@@ -33,7 +33,7 @@
 
 	  <div class="content">
 		<h1>
-		  Amber docs <span class="tiny">v0.12.3</span><br><small>Guides & API reference</small>
+		  Amber docs <span class="tiny">v0.13.0pre</span><br><small>Guides & API reference</small>
 		</h1>
 	  </div>
 	</div>