Update api_package_unorphan so that it does not fail on the first error

This allows us to submit a bunch of packages and branches and it will
process them all and report what's good and what's wrong instead of
stopping at the first error and reporting what's wrong for that entry.
Adjust the unit-tests for the api_packages_unorphan to cover the changes well
If one thing goes right when unorphaning a package, consider it all went ok
Adjust the unit-test accordingly
Allow the orphan API to keep running even if one pkg/branch combination fails

This allows one to ask for a bunch of packages to be orphaned on a bunch
of branches and all the valid ones will be while the invalid ones will be
ignored (though reported).
Adjust the unit-tests for the /api/package/orphan endpoint