Merge branch 'tr/reset-checkout-patch'

* tr/reset-checkout-patch: stash: simplify defaulting to "save" and reject unknown options Make test case number unique tests: disable interactive hunk selection tests if perl is not available DWIM 'git stash save -p' for 'git stash -p' Implement 'git stash save --patch' Implement 'git checkout --patch' Implement 'git reset --patch' builtin-add: refactor the meat of interactive_add() Add a small patch-mode testing library git-apply--interactive: Refactor patch mode code Make 'git stash -k' a short form for 'git stash save --keep-index'