Move this package to the WMF repository.

Change-Id: I20c8e4bf5b915e98156f6274826d06e30ec1a22a
Update dependencies.

* `commander` to 2.5.0
* `es6-shim` to 0.20.2
* `jshint` to 2.5.0 (and jshint added to `npm test`)
* `mocha` to 2.0.1

Change-Id: Ib7012ee66c1593398e5e335c1dcaa80352f91759
Be quiet when unzipping; don't create pipes in `P.spawn`.

Both these changes ensure that we don't block for pipe input when
unzipping large bundles.

Change-Id: Id4e14b7e4670b0d977a7cd6bc718aa0f953ab91e