Added a test for updating db items using put.
Added a test for deleting a db item.
Removed unnecessary headers.
Fixed an issue with 404 result.
Re-enabled the other tests.
Started to simplify tests and make them more expressive.
Simplified tests by extracting utility fns.
Converted over to promises for easier management of async tests.
Removed the logic that was conditional on 'expresso'.
Removed old 'espresso' tests. These are replaced by Jasmine tests now.
Updated package file to latest version of node.