Version 1.3 and "The Brothers"

Changes from version 1.2:

• Added automatic patching of packagedefinition.txt
• Better error messages for invalid JSON files
• Support for deleted content detection
• Support for the json meta format used by rpkg
• Support for framework compatibility metadata on mods and content packs
• Support for content packs adding content to chunks other than chunk0
• Support for content packs registering content in packagedefinition.txt

The unofficial content pack for Offline Elusives was updated to automatically restore "The Brothers" using the new framework features.