[PATCH 0/9] Progress with git submodule

This series replaces origin/sb/submodule-helper and is based on 5a1ba6b48a62bf55f9c8305d9850c3a8d22365c5, (Merge 'hv/submodule-config' to 'sb/submodule-helper', which includes jk/git-path and hv/submodule-config)

What changed?
* The help text of the submodule--helper was adapted to our standard,
  and removed long line, outdated docs, thanks Dscho!
  
* The run-command API was extended to be able to sync the output from
  various commands running at the same time.
  (In the previous series this was a one-shot only solution cooked for
   git submodule foreach_parallel)
   
* `git fetch recurse-submodules` will fetch the submodules in parallel!

Any feedback welcome, specially on patch 4..7

Thanks, Stefan

Stefan Beller (9):
  submodule: implement `module_list` as a builtin helper
  submodule: implement `module_name` as a builtin helper
  submodule: implement `module_clone` as a builtin helper
  thread-utils: add a threaded task queue
  run-command: add synced output
  submodule: helper to run foreach in parallel
  fetch: fetch submodules in parallel
  index-pack: Use the new worker pool
  pack-objects: Use new worker pool

 .gitignore                      |   1 +
 Documentation/fetch-options.txt |   7 +
 Makefile                        |   1 +
 builtin.h                       |   1 +
 builtin/fetch.c                 |   6 +-
 builtin/index-pack.c            |  23 +--
 builtin/pack-objects.c          | 175 ++++++-----------
 builtin/pull.c                  |   6 +
 builtin/submodule--helper.c     | 417 ++++++++++++++++++++++++++++++++++++++++
 git-submodule.sh                | 177 +++--------------
 git.c                           |   1 +
 run-command.c                   |  99 ++++++++--
 run-command.h                   |  21 ++
 submodule.c                     | 100 ++++++++--
 submodule.h                     |   2 +-
 t/t7407-submodule-foreach.sh    |  11 ++
 thread-utils.c                  | 192 ++++++++++++++++++
 thread-utils.h                  |  35 ++++
 18 files changed, 960 insertions(+), 315 deletions(-)
 create mode 100644 builtin/submodule--helper.c