Feature registries

[lorenzoh]

Closes #206.

Implements feature registries for datasets, dataset recipes and learning tasks. Depends on https://github.com/lorenzoh/FeatureRegistries.jl .

ToDo:

• [x] remove old registries and deprecate relevant functions to use the new registries
• [x] add docstrings for datasets, datarecipes, learningtasks
• [x] check documentation for references to old registries and update
• [x] add descriptions to registries so that info() gives helpful information
• [ ] update CHANGELOG
• [x] fix CI
• [x] release FeatureRegistries.jl. PR will be merged in a few days: https://github.com/JuliaRegistries/General/pull/59592

Registries

Datasets

Includes all the fastai datasets and handles downloading. Also stores size and a description.

Dataset recipes

Includes recipes to load some of the datasets into a block-based data container suitable for a (supervised) learning task.

Learning tasks

Lists learning tasks and allows filtering on domain and relevant blocks.

Finding a task with a specific target block:

[lorenzoh]

Update: now with HTML display and some docs