Lack of explanation in image-related 404 error responses

[saxtouri]

When requesting details for a non-existing image trough the API, the 404 error lacks an explanation.

This is not the case with other cyclades 404 errors, e.g. a server-related 404 will contain something like "server 9999 not found" and the same holds for networks, flavors, ips, etc.

To reproduce the issue:

Assume the image id 9999 does not exist.
Try the following:

$ kamaki image info 9999 -v -o log_data=on
> HEAD https://example.com/image/1.0/images/9999
> [...]
< 404 NOT FOUND
(empty body)

Similarly with compute/image API:

$ kamaki imagecompute info 9999 -v -o log_data=on
> GET https://example.com/compute/v2.0/images/9999
> [...]
< 404 NOT FOUND
< {"itemNotFound": {"message": "", "code": 404, "details": ""}}