add support for custom annotations

bot.py

@@ -30,6 +30,10 @@ TEMPLATE_TEXT = (
     "{{ labels.alertname }} {{ labels.instance }}"
     "{% if annotations.summary %}"
     "\n{{ annotations.summary }}"
+    "{% else %}"
+    "{% for key, value in annotations.items() %}"
+    "\n{{ key }} : {{ value }}"
+    "{% endfor %}"
     "{% endif %}"
 )
 
@@ -46,6 +50,13 @@ TEMPLATE_HTML = (
     "{% if annotations.summary %}"
     "<br/>"
     "<blockquote>{{ annotations.summary }}</blockquote>"
+    "{% else %}"
+    "<br/>"
+    "<ul>"
+    "{% for key, value in annotations.items() %}"
+    "<li><b>{{ key | capitalize }} :</b> {{ value }}</li>"
+    "{% endfor %}"
+    "</ul>"
     "{% endif %}"
 )