Adding gitignore file
Adding core services module
Moved creds file from test (where it wasn't needed) to service layer (where it was)
Added getUserById service method and added unit tests.
Added dbFake to get nock stuff out of the test file.
Added updateUser service method, no unit test yet.
Cleaned up list users test.
Added unit tests for updateUser.
Added service method for authenticate with unit tests.
Updated dbFake for new unit tests.