Use env variable to save Sentry DSN

Author: martijnrondeel

src/index.js

@@ -1,8 +1,8 @@
 import ElastalertServer from './elastalert_server';
 
-if (process.env.BITSENSOR_SENTRY_ENABLED !== 'false') {
+if (process.env.BITSENSOR_SENTRY_ENABLED !== 'false' && process.env.BITSENSOR_SENTRY_DSN !== undefined) {
   var Raven = require('raven');
-  Raven.config('http://527ee316013644b387a47f713335b085:[email protected]:9000/5').install();
+  Raven.config(process.env.BITSENSOR_SENTRY_DSN).install();
 
   Raven.context(function () {
     let server = new ElastalertServer();