Namespaces: added feature to show folder structure

Namespaces are an important feature to have a hierarchic structure for the wiki.
A new site was added that can display and navigate the folder structure.

src/templates/entry.html

@@ -3,7 +3,7 @@
 <div class="container">
     <div class="content">
         {% autoescape off %}
-	<span>{{ content }}</span>
+	{{ content }}
         {% endautoescape %}
     </div>
 </div>

src/templates/search.html

@@ -9,7 +9,7 @@
         </form>
         <div class="content">
             {% autoescape off %}
-	    <span>{{ content }}</span>
+	    {{ content }}
             {% endautoescape %}
         </div>
     </div>

src/templates/template.html

@@ -14,6 +14,7 @@
         <label for="main-menu-check" class="show-menu">&#9776;</label>
         <div class="main-menu">
             <a href="/">Startpage</a>
+            <a href="/namespace">Namespaces</a>
             <a href="/search">Search</a>
             <label for="main-menu-check" class="hide-menu">X</label>
         </div>