Make register public so we can support other servers e.g. hapi

libraries/metrics/metrics.coffee

@@ -1,5 +1,5 @@
 prom = require('prom-client')
-Register = require('prom-client').register
+
 collectDefaultMetrics = prom.collectDefaultMetrics
 
 appname = "unknown"
@@ -15,6 +15,7 @@ destructors = []
 require "./uv_threadpool_size"
 
 module.exports = Metrics =
+	register: require('prom-client').register
 	initialize: (_name) ->
 		appname = _name
 		collectDefaultMetrics({ timeout: 5000, prefix: Metrics.buildPromKey()})
@@ -60,8 +61,8 @@ module.exports = Metrics =
 
 	injectMetricsRoute: (app) ->
 		app.get('/metrics', (req, res) -> 
-			res.set('Content-Type', Register.contentType)
-			res.end(Register.metrics())
+			res.set('Content-Type', register.contentType)
+			res.end(register.metrics())
 		)
 
 	buildPromKey: (key = "")->