When the output is redirected to a file, it does not make sense to print the nice progress output.
Fixes #66
Alternative solution would be to not set up the callback in the first place. That would have to be done in two places though (for download and upload).
LGTM
Pull-Request has been merged by lsedlar
When the output is redirected to a file, it does not make sense to print
the nice progress output.
Fixes #66