protocol-engine: allow using data files with a protocol

[sanni-t]

Overview

As a user, I want to use an HTTP endpoint to send a Python protocol file and accompanying data files to the robot

• I should be able to upload a non-python data file (csv, txt, json) along with my protocol and read (and write to?) this file from my python protocol.
• Should be able to upload multiple data files and these should be recognized as such and should be associated with the protocol file

Implementation details

• The /protocols endpoint is a multi-part/form-data that accepts multiple files. You use that id to upload multiple files. They are all saved in the same directory on /tmp and associated with the same protocol ID.
• Once you are done uploading files, you can use a simulate endpoint to check the uploaded protocol
• The robot-server/ engine recognizes if the file is a data file or a python file. If it’s a data file, the PE leaves it alone and assumes the python protocol file does correct I/O in order to access its data
• Rely on nginx max file size limit

NOTE:

• uploading support files later while a protocol is running is out of scope for this ticket
• could end up supporting zip file uploads after @readywater 's UX spike

[sanni-t]

Done.