Need a better error message for failed uploads from the CLI
When uploading repository content, we just have a generic error message:
hammer repository upload-content --id 1 --path tmp/scratch.tar Failed to upload file 'scratch.tar' to repository. Please check the file and try again.
It would be nice to tell the user exactly what failed. Not sure if pulp tells us the exact error though (like failing to unzip/read a file).