間にスペースある時の対策。
$ git ls-files | fgrep .DS | xargs git rm --cached
fatal: not removing 'iTunes/iTunes' recursively without -r
$ git ls-files | fgrep .DS | xargs -I{} git rm --cached "{}"
rm '.DS_Store'
rm 'iTunes/.DS_Store'
rm 'iTunes/iTunes Media/.DS_Store'
rm 'iTunes/iTunes Media/Music/.DS_Store'
rm 'iTunes/iTunes/.DS_Store'