don't default to adding underscore to name

libraries/metrics/metrics.coffee

@@ -20,7 +20,7 @@ require "./uv_threadpool_size"
 
 module.exports = Metrics =
 	initialize: (_name) ->
-		name = _name + "_"
+		name = _name
 		collectDefaultMetrics({ timeout: 5000, prefix: name+"_"})
 
 	registerDestructor: (func) ->