[PATCH 0/3] Update sha1dc from upstream & optionally make it a submodule

This series:

Ævar Arnfjörð Bjarmason (3):
  sha1dc: update from upstream
   
   * Fixes the Big-Endian detection on Solaris SPARC (and probably
     others) which broke the build as of 2.13.0 due to sha1dc being the
     dauflt.
   
   * Includes a patch from upstream fixing unaligned access, which broke
     SPARC even more. This replaces Junio's "[PATCH] sha1dc: fix issues
     with a big endian platform"
     (<xmqq37c4xcr6.fsf_-_@gitster.mtv.corp.google.com>) with something
     which brings in upstream as-is.
   
   * Most importantly: Uses upstream code as-is with no modifications,
     which is possible due to a pull request I sent them.

   * This patch can be picked stand-alone without [23]/3.

  sha1dc: use sha1collisiondetection as a submodule

   * Since we can now use upstream code as-is let's use it as a
     submodule.
   
     Yes there are still (solvable) UX issues with submodules, but
     there's no project better equipped to deal with them than
     git.git.

  sha1dc: remove the unused sha1dc/ directory

   * Sent as a separate patch for readability. Can be squashed into
     2/3.

 .gitmodules            |   4 +
 Makefile               |  13 +-
 hash.h                 |   2 +-
 sha1collisiondetection |   1 +
 sha1dc/LICENSE.txt     |  30 ----
 sha1dc/sha1.c          |  99 +++++++++-----
 sha1dc/sha1.h          | 122 -----------------
 sha1dc/ubc_check.c     | 363 -------------------------------------------------
 sha1dc/ubc_check.h     |  44 ------
 sha1dc_git.c           |  24 ++++
 sha1dc_git.h           |  19 +++
 11 files changed, 124 insertions(+), 597 deletions(-)
 create mode 100644 .gitmodules
 create mode 160000 sha1collisiondetection
 delete mode 100644 sha1dc/LICENSE.txt
 delete mode 100644 sha1dc/sha1.h
 delete mode 100644 sha1dc/ubc_check.c
 delete mode 100644 sha1dc/ubc_check.h
 create mode 100644 sha1dc_git.c
 create mode 100644 sha1dc_git.h