Sync with maint-2.10

* maint-2.10:
  preparing for 2.10.3

Documentation/RelNotes/2.10.3.txt

@@ -0,0 +1,48 @@
+Git v2.10.3 Release Notes
+=========================
+
+Fixes since v2.10.2
+-------------------
+
+ * Extract a small helper out of the function that reads the authors
+   script file "git am" internally uses.
+   This by itself is not useful until a second caller appears in the
+   future for "rebase -i" helper.
+
+ * The command-line completion script (in contrib/) learned to
+   complete "git cmd ^mas<HT>" to complete the negative end of
+   reference to "git cmd ^master".
+
+ * "git send-email" attempts to pick up valid e-mails from the
+   trailers, but people in real world write non-addresses there, like
+   "Cc: Stable <add@re.ss> # 4.8+", which broke the output depending
+   on the availability and vintage of Mail::Address perl module.
+
+ * The code that we have used for the past 10+ years to cycle
+   4-element ring buffers turns out to be not quite portable in
+   theoretical world.
+
+ * "git daemon" used fixed-length buffers to turn URL to the
+   repository the client asked for into the server side directory
+   path, using snprintf() to avoid overflowing these buffers, but
+   allowed possibly truncated paths to the directory.  This has been
+   tightened to reject such a request that causes overlong path to be
+   required to serve.
+
+ * Recent update to git-sh-setup (a library of shell functions that
+   are used by our in-tree scripted Porcelain commands) included
+   another shell library git-sh-i18n without specifying where it is,
+   relying on the $PATH.  This has been fixed to be more explicit by
+   prefixing $(git --exec-path) output in front.
+
+ * Fix for a racy false-positive test failure.
+
+ * Portability update and workaround for builds on recent Mac OS X.
+
+ * Update to the test framework made in 2.9 timeframe broke running
+   the tests under valgrind, which has been fixed.
+
+ * Improve the rule to convert "unsigned char [20]" into "struct
+   object_id *" in contrib/coccinelle/
+
+Also contains minor documentation updates and code clean-ups.