examples: refer to nightly rustfmt in Windows-compatible way Thanks to Jun Wu for the tip. I found that the new form also gave better error messages when the nightly rustfmt wasn't installed (it told me which command to run instead of just saying "error: not a file: <some path>"). Differential Revision: https://phab.mercurial-scm.org/D7911

convert: refactor authormap into separate function for outside use Differential Revision: https://phab.mercurial-scm.org/D7732