Merge branch 'nd/ignore-then-not-ignore'

Allow a later "!/abc/def" to override an earlier "/abc" that appears in the same .gitignore file to make it easier to express "everything in /abc directory is ignored, except for ...". * nd/ignore-then-not-ignore: dir.c: don't exclude whole dir prematurely if neg pattern may match dir.c: make last_exclude_matching_from_list() run til the end