Add stacklight_environment parameter

This allows Nagios to support several environments.

https://github.com/Mirantis/mk-lab-salt-model/pull/197
diff --git a/heka/server.yml b/heka/server.yml
new file mode 100644
index 0000000..5141e40
--- /dev/null
+++ b/heka/server.yml
@@ -0,0 +1,8 @@
+parameters:
+  _param:
+    stacklight_environment: ${_param:cluster_domain}
+  heka:
+    server:
+      extra_fields:
+        environment_label: ${_param:stacklight_environment}
+