Add the missing ArgumentParser types on Reference Scripts

[datumbox]

🚀 The feature

Quite a few arguments on the Reference Scripts are missing the type parameter. Most of them seem to be strings.

Examples:

vision/references/classification/train.py

Lines 379 to 380 in e08c9e3

	parser.add_argument("--output-dir", default=".", help="path where to save")
	parser.add_argument("--resume", default="", help="resume from checkpoint")

vision/references/detection/train.py

Line 80 in e08c9e3

parser.add_argument("--lr-scheduler", default="multisteplr", help="the lr scheduler (default: multisteplr)")

vision/references/segmentation/train.py

Line 247 in e08c9e3

parser.add_argument("--dist-url", default="env://", help="url used to set up distributed training")

It would be good to add them and improve the arguments by providing better descriptions on the help argument.

[puhuk]

If it is ok, I want to resolve this issue :)

[datumbox]

You got it @puhuk. Looking forward to your PR.