Immediate tasks

• Move to IForgeRegistry. This allows persistence between worlds and servers.
• Make the API look like an API. It currently looks like a big mish-mash of classes.
• Fix issues with some models not rendering correctly in the GUI. Most work, but others are broken (eg: Beacon)
• Move entries from a List<EntryAbstract> to a Map<ResourceLocation, EntryAbstract>. This will make entry lookups for IGuideLinked much cleaner.
• Clean up visuals a bit. They're not horrible, but they could definitely be better.
• Clean up the JSON system. It's currently a huge chore to write JSON books.

Down the road tasks

• In-game guide editing (For JSON system)
• HTML exporter

Stretch features

• Support for more guide formats. (Markdown, HTML, etc)