Uploads a file and stores it on the job. Send the request as multipart/form-data with these
fields:

• document[file]: the file itself, up to 50 MB. Most file types are accepted; HTML, XML and SVG
  files are refused.
• document[title] (required): the name shown in RoofRabbit.
• document[document_type] (required): the category, for example contract, estimate,
  invoice, permit_application, inspection_report, storm_report, proposal,
  contingency_agreement or other.
• document[description] (optional): a longer note about the file.
• document[tag_list] (optional): a comma-separated list of tags, at most 20 tags of up to 40
  characters each. Tags are stored in lowercase.

The document is filed into the company's default folder for its type, and an entry noting the
upload is added to the job's activity log. The user behind the token is recorded as the uploader.
The token's role must be able to work on sales or production jobs.