feat(packages) - cleanup schema, use the same field names as reuters
feat(packages) - change residRef format
feat(packages) - fix link update to update only the needed property instead of the whole doc
allow packages without references to be added
feat(packages) - add versioning support
packages - improve logging
Merge branch 'fix-patch' into packages
feat(packages) - check root group references
feat(packages) - validate root group on PATCH.
Merge pull request #451 from superdesk/packages

feat(packages) - update the schema to allow reuters like newsml schema