Increase download speed

[analog-cbarber]

The code currently uses a chunk size of 1024 bytes. Consider using a much larger size (1MB)

Also consider using a session.

See https://stackoverflow.com/questions/23369625/ideal-chunk-size-for-python-requests

[analog-cbarber]

Playing with this a bit I really don't see any real performance difference when I change the chunk size on my machine and network, but using a common requests.Session object can make a big difference. I saw something like a 30% to 400% speedup when using a session. I think it may be a bigger win when packages are small.

[analog-cbarber]

Fixed in https://github.com/analog-garage/conda-mirror/tree/ag-faster-download

[xhochy]

This sounds very useful as this should get the TLS connection alive. This is probably the major cost for very small packages.