Merge branch 'ar/maint-mksnpath' into ar/mksnpath

Merge branch 'ar/maint-mksnpath' into ar/mksnpath

* ar/maint-mksnpath:
  Use git_pathdup instead of xstrdup(git_path(...))
  git_pathdup: returns xstrdup-ed copy of the formatted path
  Fix potentially dangerous use of git_path in ref.c
  Add git_snpath: a .git path formatting routine with output buffer

Conflicts:
	builtin-revert.c
	refs.c
	rerere.c