Merge branch 'js/range-diff-one-side-only'

The "git range-diff" command learned "--(left|right)-only" option to show only one side of the compared range. * js/range-diff-one-side-only: range-diff: offer --left-only/--right-only options range-diff: move the diffopt initialization down one layer range-diff: combine all options in a single data structure range-diff: simplify code spawning `git log` range-diff: libify the read_patches() function again range-diff: avoid leaking memory in two error code paths