Expand a little the packager API tests
Rollback early in case of error
Fix authentication of the Packages API and the json output in case of error
Make sure the get_acl_package always return a list
Adjust unit-test to the new get_acl_package
Work up the Package API

- Add the page, limit and count argument to the api_package_list
- Add authentication required for the endpoints requiring it
- Update variable name where required
- Expand the api_package_info to return a 404 in case the package does not
exist.
Add unit-tests for the Package API
Expand unit-test coverage of the Extras API