better downloading experience fo novice users

[bit-scientist]

I can see the following the Readme for downloading the rf100 into local env:

chmod 770 ./scripts/download_datasets.sh
./scripts/download_datasets.sh
./scripts/download_datasets.sh -f yolov5 $ change format
./scripts/download_datasets.sh -l <path_to_my_location> change download location

I think, for novice linux OS users, these lines are confusing as they do basically same thing. It would be more proper if it gave options.

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