Update dependencies.

* `commander` to 2.5.0
* `es6-shim` to 0.20.2
* `prfun` to 1.0.1
* `jshint` to 2.5.0
* `request` to 2.47.0

Change-Id: I825c2c8bee303f0d8ef4ab6b03e891491a18be64