refs #9178, refs #8988
With 7353c87d7f we use Bluebird globally for Promises. Therefore, the request lib doesn't need to be wrapped in a bluebird Promise anymore.
This was originally done, so we can work with catch predicated in our image-size lib.
Updated the tests to proof, that the catch predicates work.
The tests fail, as soon as the Promise overwrite is commented out.