make links clickable in task descriptions

app/templates/tasks.html

@@ -12,7 +12,17 @@
                 </a>
                 <b>
                     {% if task.description != None %}
-                        {{ task.description }}
+                        {% set description = task.description %}
+                        {% set url_regex = '(https?://[^\s]+)' %}
+
+                        {% set match = re.search(url_regex, description) %}
+                        {% if match %}
+                            {% set url = match.group(0) %}
+                            {% set rest = description[match.end(0):] %}
+                            <p>{{ description[:match.start(0)] }}<a href="{{ url }}">{{ url }}</a>{{ rest }}</p>
+                        {% else %}
+                            <p>{{ description }}</p>
+                        {% endif %}
                     {% endif %}
                 </b>
                 <div>