Add zero folders found check, thus no benchmarks to be displayed

_layouts/benchmarks.html

@@ -9,8 +9,8 @@
                 <img class="logo" src="{{site.baseurl}}/assets/img/rust-python-logo.svg" alt="RustPython Logo">
             </div>
             <div class="pl-md-2">
-                <div class="section-title">Benchmarks</div>
-                <div class="title">{{ site.title }} {{ page.title | escape }}</div>
+                <div class="section-title">RustPython</div>
+                <div class="title">{{ page.title | escape }}</div>
                 <small>{{ site.benchmarks-intro }}</small>
             </div>
         </div>
@@ -22,8 +22,6 @@
         {{ content }}
     </div>
 
-    <!-- TODO clean up this code a bit -->
-
     {% assign folders = "" | split: ", " %}
     {% for image in site.static_files %}
     {% if image.path contains 'criterion/' %}
@@ -48,9 +46,11 @@
     {% endfor%}
     {% assign folders = folders | uniq %} -->
 
-    <!-- TODO check if the folders list is empty, if so, display corresponding message -->
-    <!-- TODO add text that explains the violin plots -->
-
+    {% if folders.size == 0 %}
+    <p style="color: red;">There are no benchmarks to be displayed.</p>
+    <p>This shouldn't be happening, please contact one of the maintainers
+        through <a href="https://gitter.im/rustpython/Lobby">Gitter</a> to report this problem.</p>
+    {% else %}
     <ul class="tab" data-tab="benchmarks">
         {% for folder in folders %}
         <li {% if forloop.index==1 %} class="active" {% endif %}>
@@ -65,12 +65,13 @@
             {% for image in site.static_files %}
             {% if image.path contains folder %}
             <figure>
-                <img src="{{ site.baseurl }}{{ image.path }}" alt="image" width="50%" />
+                <img src="{{ site.baseurl }}{{ image.path }}" alt="image" />
                 <figcaption>{{ image.name }}</figcaption>
             </figure>
             {% endif %}
             {% endfor%}
         </li>
         {% endfor%}
     </ul>
+    {% endif %}
 </div>

benchmarks.markdown

@@ -3,4 +3,8 @@ layout: benchmarks
 title: Benchmarks
 ---
 
-RustPython is an awesome Python interpreter! On this page you can see how it compares to CPython.
+This page displays some benchmarks that determine the performance of RustPython.
+
+Most of these benchmarks compare RustPython to CPython.
+
+More information about the benchmarks can be found on [the RustPython GitHub repo](https://github.com/RustPython/RustPython/tree/master/benches).