stats: Add stats page

* add stats_table_data() function on the backend
* add stats HTML page and route

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

chanbans/templates/stats.html

@@ -0,0 +1,36 @@
+{% extends "base.html" %}
+
+{% block title %}Stats{% endblock title %}
+
+{% block main %}
+    <h2>Statistics</h2>
+    <div class="infobox">
+        <h4>Histogram</h4>
+        <p>
+        <img src="{{static_url("histogram.svg")}}" width="33%" />
+        </p>
+        <p>
+        <a target="_blank" href="{{static_url("histogram.svg")}}">Click here to see the full histogram view</a>
+        </p>
+        <hr/>
+        <h4>Table</h4>
+        <p>
+        <table>
+            <thead>
+                <tr>
+                    <th>Board</th>
+                    <th>Bans</th>
+                </tr>
+            </thead>
+            <tbody>
+                {% for row in stats_table_data() %}
+                <tr>
+                    <td>{{row['board']}}</td>
+                    <td>{{row["bans"]}}</td>
+                </tr>
+                {% endfor %}
+            </tbody>
+        </table>
+        </p>
+    </div>
+{% endblock main %}