GitLab

* refactor dataloader

* cleanup + add docs

* change arg

* renamed Collator and added testing

* parametrized test for Collator

* appease pre-commit

* added edge case batch 0 (no batching)

* fix typos

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Co-authored-by: Hailey Schoelkopf <65563625+haileyschoelkopf@users.noreply.github.com>