Don't show news link til there is news.

_layouts/default.html

@@ -32,9 +32,11 @@
 
                     <div class="navbar-collapse collapse">
                         <ul class="nav navbar-nav">
+                            {% if site.posts != empty %}
                             <li>
                                 <a href="{{page.root}}/news">News</a>
                             </li>
+                            {% endif %}
 
                             <li class="dropdown">
                                 <a href="{{page.root}}/engine" class="dropdown-toggle" data-toggle="dropdown">Engine<i class="fa fa-angle-down"></i></a>