Add support for --range-start and --range-end

[trixnz]

IDEs often have the ability to format a specific region of text, rather than the whole document. One could naively format just the selection and insert it into the document, but the IDE is generally going to be unaware of the correct indentation level and other restrictions that the language may have.

These options should run the full printer pass, but only print code that falls within the ranges.