JSONL support

[cretz]

What was changed

• Add --output jsonl option which removes indentation/newlines from JSON output
• Add printer StartList and EndList
  • In --output json mode, this will add [ at the beginning, commas before newline of each successive object, and ] at the end so that it will parse as an array
  • In --output jsonl mode, this will do nothing special (indention is already off, just allows normal use of repeated JSON values)
• Added StartList and EndList to workflow list, batch list, and cluster list

(note, there may be an outstanding flaky batch test we are researching)

Checklist

1. Closes #448

[cretz]

Merging, but I do not hold the use of empty-jsonindent-means-jsonl nor the use of list vs array as a strong opinion if anyone really wants them changed.