Add new aspects to World Item Importer so that it can read the NBT data of the item entity itself rather than that of the item

[AlisonHuang777]

Issue type:

• :heavy_plus_sign: Feature request

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Short description:

As the title suggested. The main reason I want this feature is that, for example, Create's Bulk Processing recipes involves dropping item in front of the fan, and when doing so, CreateData.Processing will be added to ForgeData which only presents in the item entity. Making use of this feature, one can make the Importer pick up item entities that matches the predicate .ForgeData.CreateData.Processing.Time == -1 which indicates that the item has finished processing. Apart from this example, one can also utilize the vanilla tags to achieve various applications.

[rubensworks]

Thanks for the suggestion!