downgraded dev dependency event-stream

Author: Annemarie

package.json

@@ -40,7 +40,7 @@
     "browserify": "^14.1.0",
     "eslint": "^3.19.0",
     "eslint-plugin-react": "^6.10.3",
-    "event-stream": "^3.3.4",
+    "event-stream": "3.3.4",
     "gulp": "^3.9.0",
     "gulp-babel": "^6.1.0",
     "gulp-clean": "^0.3.1",