This of course breaks the API, but hopefully we stay consistent
from this point forward

We trap the low level OBS api calls via a callback and
check for success. If error returned, parse the OBS error response
and raise an exception.

When an api object makes an API request to the OBS server, in
addition to returning the results, it sends a reference to
itself to the registered callback function (if set).

We use this to track the last api object called so we can access
the last raw request response.

Move class to own file and enhance tests

We don't need to create flags - just read and parse them from
the project meta config. Remove the unneeded functionality and
enhance the structure. All flags from a project and package
are accessible via a single RepoFlags object.