fix: data logger now called from main, plot in thread

app/templates/fridges.html

@@ -17,7 +17,7 @@
                     {% set fils = "log_%s.png" % sensor.id %}
                     <img src="{{ url_for('static', filename=fils) }}" /><br>
                 </div>
-                {% endfor %}b
+                {% endfor %}
             </div>
         </div>
         {% endfor %}