The indent function was stripping out newlines, causing multi-element
lists and maps to be rendered incorrectly.
We were also not quoting strings in these nested structures, leading to
weird behavior if any expression punctuation or newlines were present in
these strings.
This part of Terraform will get a more serious overhaul as part of
switching to the new parser/interpreter implementation but this is a
tactical fix to make the results of this command more usable in the
short term.