Add missing macros.html

appengine/machine_provider/templates/macros.html

Index: appengine/machine_provider/templates/macros.html
diff --git a/appengine/machine_provider/templates/macros.html b/appengine/machine_provider/templates/macros.html
new file mode 100644
index 0000000000000000000000000000000000000000..5e85c7c0e56dbbbac53f3b70d579a0c182694478
--- /dev/null
+++ b/appengine/machine_provider/templates/macros.html
@@ -0,0 +1,7 @@
+{% macro render_message(message) %}
+  {% for field in message.all_fields()|sort(attribute='name') %}
+    {% if message.get_assigned_value(field.name) %}
+      <strong>{{field.name}}</strong>: {{message.get_assigned_value(field.name)}}<br />
+    {% endif %}
+  {% endfor %}
+{% endmacro %}