Closes #355 | Add Dataloader TotalDefMeme

[akhdanfadh]

Closes #355

There are 2 tasks with different schemas. The OCR task is intended for all the images, but the ImageClassification task is only for those having pillar_stances attribute since the dataset is about pillar classification, CMIIW.

Also, the new image schema is added here instead of in a new PR for example sake. Once checked and okay, I will add a new PR for adding the new schema, and remove the relevant files from this PR.

Also again, similar to #556 and #566: I use third-party libraries to download the GDrive data, i.e., pip install gdown, because it is more reliable than the dl_manager. Similarly, I also store the downloaded data in data/total_defense_meme/. I am aware that I should make or wait for a PR on those two things, so currently waiting for further instruction.

Checkbox

• [x] Confirm that this PR is linked to the dataset issue.
• [x] Create the dataloader script seacrowd/sea_datasets/my_dataset/my_dataset.py (please use only lowercase and underscore for dataset naming).
• [x] Provide values for the _CITATION, _DATASETNAME, _DESCRIPTION, _HOMEPAGE, _LICENSE, _URLs, _SUPPORTED_TASKS, _SOURCE_VERSION, and _SEACROWD_VERSION variables.
• [x] Implement _info(), _split_generators() and _generate_examples() in dataloader script.
• [x] Make sure that the BUILDER_CONFIGS class attribute is a list with at least one SEACrowdConfig for the source schema and one for a seacrowd schema.
• [x] Confirm dataloader script works with datasets.load_dataset function.
• [x] Confirm that your dataloader script passes the test suite run with python -m tests.test_seacrowd seacrowd/sea_datasets/<my_dataset>/<my_dataset>.py.
• [ ] If my dataset is local, I have provided an output of the unit-tests in the PR (please copy paste). This is OPTIONAL for public datasets, as we can test these without access to the data files.

[akhdanfadh]

@holylovenia I've done changing what can be done. See my comments on your review.

Let's move the new tasks and schema to another PR.

I'll make the new PR once everything on the dataloader part is done and reviewed.