merge(third_party/git): Merge squashed git subtree at v2.23.0

Merge commit '1b593e1ea4' as 'third_party/git'

third_party/git/Documentation/RelNotes/1.6.0.3.txt

@@ -0,0 +1,117 @@
+GIT v1.6.0.3 Release Notes
+==========================
+
+Fixes since v1.6.0.2
+--------------------
+
+* "git archive --format=zip" did not honor core.autocrlf while
+  --format=tar did.
+
+* Continuing "git rebase -i" was very confused when the user left modified
+  files in the working tree while resolving conflicts.
+
+* Continuing "git rebase -i" was also very confused when the user left
+  some staged changes in the index after "edit".
+
+* "git rebase -i" now honors the pre-rebase hook, just like the
+  other rebase implementations "git rebase" and "git rebase -m".
+
+* "git rebase -i" incorrectly aborted when there is no commit to replay.
+
+* Behaviour of "git diff --quiet" was inconsistent with "diff --exit-code"
+  with the output redirected to /dev/null.
+
+* "git diff --no-index" on binary files no longer outputs a bogus
+  "diff --git" header line.
+
+* "git diff" hunk header patterns with multiple elements separated by LF
+  were not used correctly.
+
+* Hunk headers in "git diff" default to using extended regular
+  expressions, fixing some of the internal patterns on non-GNU
+  platforms.
+
+* New config "diff.*.xfuncname" exposes extended regular expressions
+  for user specified hunk header patterns.
+
+* "git gc" when ejecting otherwise unreachable objects from packfiles into
+  loose form leaked memory.
+
+* "git index-pack" was recently broken and mishandled objects added by
+  thin-pack completion processing under memory pressure.
+
+* "git index-pack" was recently broken and misbehaved when run from inside
+  .git/objects/pack/ directory.
+
+* "git stash apply sash@{1}" was fixed to error out.  Prior versions
+  would have applied stash@{0} incorrectly.
+
+* "git stash apply" now offers a better suggestion on how to continue
+  if the working tree is currently dirty.
+
+* "git for-each-ref --format=%(subject)" fixed for commits with no
+  no newline in the message body.
+
+* "git remote" fixed to protect printf from user input.
+
+* "git remote show -v" now displays all URLs of a remote.
+
+* "git checkout -b branch" was confused when branch already existed.
+
+* "git checkout -q" once again suppresses the locally modified file list.
+
+* "git clone -q", "git fetch -q" asks remote side to not send
+  progress messages, actually making their output quiet.
+
+* Cross-directory renames are no longer used when creating packs.  This
+  allows more graceful behavior on filesystems like sshfs.
+
+* Stale temporary files under $GIT_DIR/objects/pack are now cleaned up
+  automatically by "git prune".
+
+* "git merge" once again removes directories after the last file has
+  been removed from it during the merge.
+
+* "git merge" did not allocate enough memory for the structure itself when
+  enumerating the parents of the resulting commit.
+
+* "git blame -C -C" no longer segfaults while trying to pass blame if
+   it encounters a submodule reference.
+
+* "git rm" incorrectly claimed that you have local modifications when a
+  path was merely stat-dirty.
+
+* "git svn" fixed to display an error message when 'set-tree' failed,
+   instead of a Perl compile error.
+
+* "git submodule" fixed to handle checking out a different commit
+  than HEAD after initializing the submodule.
+
+* The "git commit" error message when there are still unmerged
+  files present was clarified to match "git write-tree".
+
+* "git init" was confused when core.bare or core.sharedRepository are set
+  in system or user global configuration file by mistake.  When --bare or
+  --shared is given from the command line, these now override such
+  settings made outside the repositories.
+
+* Some segfaults due to uncaught NULL pointers were fixed in multiple
+  tools such as apply, reset, update-index.
+
+* Solaris builds now default to OLD_ICONV=1 to avoid compile warnings;
+  Solaris 8 does not define NEEDS_LIBICONV by default.
+
+* "Git.pm" tests relied on unnecessarily more recent version of Perl.
+
+* "gitweb" triggered undef warning on commits without log messages.
+
+* "gitweb" triggered undef warnings on missing trees.
+
+* "gitweb" now removes PATH_INFO from its URLs so users don't have
+  to manually set the URL in the gitweb configuration.
+
+* Bash completion removed support for legacy "git-fetch", "git-push"
+  and "git-pull" as these are no longer installed.  Dashless form
+  ("git fetch") is still however supported.
+
+Many other documentation updates.