Resolve dependency module requiring

* es5 style module exports
* remove script tag require
* webpack config ProvidePlugin

Note that this commit only fix JavaScript module loading runtime error.

package.json

@@ -64,6 +64,7 @@
     "morgan": "^1.7.0",
     "mysql": "^2.11.1",
     "node-uuid": "^1.4.7",
+    "ot": "0.0.15",
     "passport": "^0.3.2",
     "passport-dropbox-oauth2": "^1.1.0",
     "passport-facebook": "^2.1.1",
@@ -84,6 +85,7 @@
     "sequelize-cli": "^2.4.0",
     "shortid": "2.2.6",
     "socket.io": "1.4.8",
+    "socket.io-client": "^1.4.8",
     "sqlite3": "^3.1.4",
     "store": "^1.3.20",
     "string": "^3.3.1",