For some reason, I didn't figure out that it's completely possible having more than a single World during runtime.
From now on, each World will hold PresetBlocks for itself.
Not just that, I fixed an issue in which when a Chunk that held PresetBlocks unloaded, and was later loaded again, it loaded just without the PresetBlocks (you would only see the invisible blocks / barriers)

Localization is still not done

Changes since v1.2.3

• e59c51f Loads PresetBlocks again if Chunk was reloaded
• c0df0ce Splits PresetBlockAssetDirector into worlds
• c7a1fb9 Refactored blockasset to presetblock
• a21f5ee Uses BlobLib's DisplayOperator, Adds DesignDisplayOperator (for future usage), Adds DesignDisplayOperatorReader, PresetBlockAsset correctly returns its DisplayElementType