Feat (script): Added pre-generated `captions.tsv`

Feat (script): Added initial reproduction README.

Feat (script): Added option to validate on MLPerf validation set & to load a pre-quantized checkpoint.

Fix (script): Updated dependencies.

Feat (script/env): Added conda environment YAMLs

Fix (script/env): added pandas requirement.

Reorg (minimal): moved minimal script to sub-directory.