[npm] Update to stacktrace-parser@0.1.3 and ws@0.8.0 to satisfy io.js 3 / Node 4

Summary:
The previous version of stacktrace-parser 0.1.2 had an line in its package.json file that required Node <= 2.x. That line was removed, so it no longer warns on io.js 3.x or Node 4.x.

Similarly, ws 0.8.0 was published with support for the new V8, so it compiles with io.js 3.x and therefore should work with Node 4.x.

Updated the Travis file as well to run on io.js 3.x.

Fixes #2258, #2455

Closes https://github.com/facebook/react-native/pull/2398
Github Author: James Ide <ide@jameside.com>

package.json

@@ -69,12 +69,12 @@
     "sane": "^1.1.2",
     "semver": "^4.3.6",
     "source-map": "0.1.31",
-    "stacktrace-parser": "frantic/stacktrace-parser#493c5e5638",
+    "stacktrace-parser": "0.1.3",
     "uglify-js": "2.4.16",
     "underscore": "1.7.0",
     "wordwrap": "^1.0.0",
     "worker-farm": "^1.3.1",
-    "ws": "^0.7.2",
+    "ws": "0.8.0",
     "yargs": "1.3.2",
     "yeoman-environment": "^1.2.7",
     "yeoman-generator": "^0.20.2"