#3 need to verify already-downloaded files

[Kris Raney]

Currently nothing is done to verify a file is the right
size, has the right checksum, etc. This would be useful
after the download and more importantly before skipping
a file that's already present. As an added bonus, it
would be nice to resume the download of a partial file,
rather than starting over, (or skipping it entirely, as
it does now...)

[Kris Raney]

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will resume a partially downloaded file. still doesn't check
whether the partial part already downloaded is correct.