add if statment around traceagenet and bump to 2.0.8

libraries/metrics/metrics.coffee

@@ -1,5 +1,5 @@
-traceAgent = require('@google-cloud/trace-agent')
 debugAgent = require('@google-cloud/debug-agent')
+traceAgent = require('@google-cloud/trace-agent')
 
 prom = require('prom-client')
 Register = require('prom-client').register
@@ -21,6 +21,7 @@ module.exports = Metrics =
 	initialize: (_name) ->
 		appname = _name
 		collectDefaultMetrics({ timeout: 5000, prefix: Metrics.buildPromKey()})
+		if process.env['ENABLE_TRACE_AGENT'] == "true"
 			traceAgent.start()
 		debugAgent.start({
 			serviceContext: {

libraries/metrics/package.json

@@ -1,6 +1,6 @@
 {
   "name": "metrics-sharelatex",
-  "version": "2.0.7",
+  "version": "2.0.8",
   "description": "A drop-in metrics and monitoring module for node.js apps",
   "repository": {
     "type": "git",