fix(config): make it simpler

Author: gergelyke

lib/utils/configReader.js

@@ -1,6 +1,7 @@
 var path = require('path');
 
 var extend = require('lodash/object/extend');
+var defaults = require('lodash/object/defaults');
 
 var collectorConfig = require('../config');
 
@@ -32,10 +33,7 @@ function getConfig() {
     config.reporter = require('../reporters')[reporterType].create(reporterConfig);
   }
 
-  config.appName = collectorConfig.appName || config.appName;
-
-  config.collectInterval = collectorConfig.collectInterval;
-  config.sampleSize = collectorConfig.sampleSize;
+  config = defaults({}, collectorConfig, config);
 
   //check if everything is ok with config
   if (!config.appName) {