cmd: prometheus job type and Task instrumentation

refs #67

cmd/config_parse.go

@@ -179,6 +179,8 @@ func parseJob(c JobParsingContext, i map[string]interface{}) (j Job, err error)
 		return parseSourceJob(c, name, i)
 	case JobTypeLocal:
 		return parseLocalJob(c, name, i)
+	case JobTypePrometheus:
+		return parsePrometheusJob(c, name, i)
 	default:
 		panic(fmt.Sprintf("implementation error: unknown job type %s", jobtype))
 	}