Now grunt test fails. Need to install supertest

Now grunt test fails. Need to install supertest. Supertest is a way of
doing HTTP assertions more easily via super-agent. The motivation for
HTTP with this module is to provide a high-level abstraction for testing
HTTP, while still allowing you to drop dwon to the lower-level API
provided by super-agent (this text is copied from supertest npm page).

Contact: joaquin@isla.io