[PATCH v4 0/8] extend smudge/clean filters with direct file access (for pu)

This is the same as v3, except rebased on top of tb/convert-peek-in-index to fix a build failure in pu.

Joey Hess (8):
  clarify %f documentation
  add smudgeToFile and cleanFromFile filter configs
  use cleanFromFile in git add
  use smudgeToFile in git checkout etc
  warn on unusable smudgeToFile/cleanFromFile config
  better recovery from failure of smudgeToFile filter
  use smudgeToFile filter in git am
  use smudgeToFile filter in recursive merge

 Documentation/config.txt        |  18 ++++-
 Documentation/gitattributes.txt |  42 ++++++++++++
 builtin/apply.c                 |  16 +++++
 convert.c                       | 147 +++++++++++++++++++++++++++++++++++-----
 convert.h                       |  11 +++
 entry.c                         |  53 +++++++++++----
 merge-recursive.c               |  42 +++++++++---
 sha1_file.c                     |  44 ++++++++++--
 t/t0021-conversion.sh           | 115 +++++++++++++++++++++++++++++++
 9 files changed, 441 insertions(+), 47 deletions(-)