Introducing jqfmt: A Tool for Formatting jq Commands

I wrote jqfmt to help add line breaks in sensible locations while reading (or writing!) jq.

At time of initial development, I naturally turned to https://github.com/itchyny/gojq expecting to be able to generate and walk a syntax tree—but gojq didn't seem to provide an AST that could be "walked," and it doesn't export its parsing logic to be used in library form.