Sync with 1.8.1.3

Documentation/RelNotes/1.8.1.3.txt

@@ -12,6 +12,14 @@ Fixes since v1.8.1.2
  * Command line completion code was inadvertently made incompatible with
    older versions of bash by using a newer array notation.
 
+ * Scripts to test bash completion was inherently flaky as it was
+   affected by whatever random things the user may have on $PATH.
+
+ * A fix was added to the build procedure to work around buggy
+   versions of ccache broke the auto-generation of dependencies, which
+   unfortunately is still relevant because some people use ancient
+   distros.
+
  * We used to stuff "user@" and then append what we read from
    /etc/mailname to come up with a default e-mail ident, but a bug
    lost the "user@" part.
@@ -22,7 +30,18 @@ Fixes since v1.8.1.2
  * Attempt to "branch --edit-description" an existing branch, while
    being on a detached HEAD, errored out.
 
+ * "git cherry-pick" did not replay a root commit to an unborn branch.
+
+ * We forgot to close the file descriptor reading from "gpg" output,
+   killing "git log --show-signature" on a long history.
+
  * "git rebase --preserve-merges" lost empty merges in recent versions
    of Git.
 
+ * Rebasing the history of superproject with change in the submodule
+   has been broken since v1.7.12.
+
+ * A failure to push due to non-ff while on an unborn branch
+   dereferenced a NULL pointer when showing an error message.
+
 Also contains various documentation fixes.