Merge branch 'maint'

* maint:
  Update release notes for 1.6.0.3
  checkout: Do not show local changes when in quiet mode
  for-each-ref: Fix --format=%(subject) for log message without newlines
  git-stash.sh: don't default to refs/stash if invalid ref supplied
  maint: check return of split_cmdline to avoid bad config strings

diff --cc builtin-checkout.c
Simple merge

diff --cc builtin-for-each-ref.c
Simple merge

diff --cc builtin-merge.c
Simple merge

diff --cc git.c
Simple merge