Update third_party/protobuf to protobuf-v3.0.0-beta-3

third_party/protobuf/js/package.json

 {
   "name": "google-protobuf",
-  "version": "3.0.0-alpha.5",
+  "version": "3.0.0-alpha.6",
   "description": "Protocol Buffers for JavaScript",
-  "main": "debug.js",
+  "main": "google-protobuf.js",
   "dependencies": {
-    "google-closure-library": "~20151015.0.0",
+    "google-closure-library": "~20160125.0.0",
     "gulp": "~3.9.0",
     "jasmine": "~2.4.1"
   },
-  "devDependencies": {},
+  "devDependencies": {
+    "google-closure-compiler": "~20151216.2.0",
+    "glob": "~6.0.4"
+  },
   "scripts": {
-    "test": "./node_modules/gulp/bin/gulp.js test"
+    "test": "node ./node_modules/gulp/bin/gulp.js test"
   },
   "repository": {
     "type": "git",
     "url": "https://github.com/google/protobuf/tree/master/js"
   },
   "author": "",
   "license": "Apache-2.0"
 }