WIP - Allow multiple files to be uploaded in one request.

curl -F "data=@file1.csv;type=text/csv" \
     -F "data=@file2.csv;type=text/csv" \
     -F "data=@file3.csv;type=text/csv"
Don't return a Location header.
fix issue with arg type.
Merge pull request #141 from MastodonC/feature/multi-file-upload

Allow multiple files to be uploaded in one request.