Add Ability To Upload/Copy To Subdirectory

[juklucas]

We need the ability to upload to a subdirectory recursively like so:

ssds staging upload \
    --deployment default \
   --submission-id 661e6bb2-04d3-4712-b6de-c42eeb8d63ba \
    --name EMBL_STRANDSEQ \
    --dst-dir HG01888 \
    s3://human-pangenomics/HG01888 

So when I attempt this upload to the same submission it does not throw an error:

ssds staging upload \
    --deployment default \
    --submission-id 661e6bb2-04d3-4712-b6de-c42eeb8d63ba \
    --name EMBL_STRANDSEQ \
    --dst-dir HG01891 \
    s3://human-pangenomics/HG01891

[xbrianh]

closed via #161