Accomodate multiple zip file downloads

[RY4GIT]

NSIDC server divides the download into multiple files if the request is too large.

If you do not specify the sub-request number as "....zip?#" (as in the current code), only sub-request no.1 will be downloaded.
This pull request allows downloading of multiple zip files created in one request.

P.S. Thank you the NSIDC team for making data accessible for Python users!

[asteiker]

@RY4GIT Thank you for this PR. It's a great feature to include support of these large "chunked" zip files! I started to test it out today and I am confirming with my colleagues on our multi zip file limits. We may not actually have a max of 4, in which case we can modify this so there is no hard limit depending on how the system handles these. I will take another look after I have more information on our ordering system.

[RY4GIT]

@RY4GIT Thank you for this PR. It's a great feature to include support of these large "chunked" zip files! I started to test it out today and I am confirming with my colleagues on our multi zip file limits. We may not actually have a max of 4, in which case we can modify this so there is no hard limit depending on how the system handles these. I will take another look after I have more information on our ordering system.

I see. All sound good to me, and thank you for reviewing this PR!

[asteiker]

@RY4GIT I just wanted you to know that I wasn't able to fully address this before I head offline through March 17th. I will circle back when I return to get this merged - thank you for your patience.