feat: Download coco visual genome data

[Ino-Ichan]

feat: Download coco visual genome data

Description

Purpose of the PR

• To download and preprocess coco/stair and japanese visual genome datasets.

Related Issue(s)

• Nothing

Changes

• Add scripts to dwonload and preprocess coco/stair and japanese visual genome datasets.
• Update README in the heron/datasets.
• Remove jupyter notebooks used for preprocessing the datasets previously.

Model/Algorithm Performance

• Nothing

Dependencies

• No change

Reviewer Notes

• The two scripts worked fine in my environment.
• Please point out any inconsistencies or unnatural parts.

Confirmed

• [x] I have updated the documentation accordingly.
• [x] I have adhered to the coding standards and guidelines of this project.
• [x] I have added comments, especially in hard-to-understand areas.

[Ino-Ichan]

@kotarotanahashi I updated the followings:

• Download scripts will now always download th data directory in the project's home.
• The post-download directory structure is detailed in the dataset's README.