A few scripts (both in production and tests) incorrectly redirected
their error output.  These have been corrected.

* tz/redirect-fix:
  rebase: fix stderr redirect in apply_autostash()
  t/lib-gpg: fix gpgconf stderr redirect to /dev/null

"git notes" sent its error message to its standard output stream,
which was corrected.

* tz/notes-error-to-stderr:
  notes: send "Automatic notes merge failed" messages to stderr

The three-way merge performed by "git cherry-pick" was confused
when a new submodule was added in the meantime, which has been
fixed (or "papered over").

* sb/test-cherry-pick-submodule-getting-in-a-way:
  merge-recursive: handle addition of submodule on our side of history
  t/3512: demonstrate unrelated submodule/file conflict as cherry-pick failure

"git apply --inaccurate-eof" when used with "--ignore-space-change"
triggered an internal sanity check, which has been fixed.

* rs/apply-inaccurate-eof-with-incomplete-line:
  apply: update line lengths for --inaccurate-eof

When "git rebase" prepared an mailbox of changes and fed it to "git
am" to replay them, it was confused when a stray "From " happened
to be in the log message of one of the replayed changes.  This has
been corrected.

* ew/rebase-mboxrd:
  rebase: use mboxrd format to avoid split errors

Recent update to the refs infrastructure implementation started
rewriting packed-refs file more often than before; this has been
optimized again for most trivial cases.

* mh/avoid-rewriting-packed-refs:
  files-backend: don't rewrite the `packed-refs` file unnecessarily
  t1409: check that `packed-refs` is not rewritten unnecessarily

A test update.

* cb/t4201-robustify:
  t4201: make use of abbreviation in the test more robust

Replace the mailing address of FSF to a URL, as FSF prefers.

* tz/fsf-address-update:
  Replace Free Software Foundation address in license notices
  Replace Free Software Foundation address in license notices

Some error messages did not quote filenames shown in it, which have
been fixed.

* sr/wrapper-quote-filenames:
  wrapper.c: consistently quote filenames in error messages

"git rebase -i" recently started misbehaving when a submodule that
is configured with 'submodule.<name>.ignore' is dirty; this has
been corrected.

* bw/rebase-i-ignored-submodule-fix:
  wt-status: actually ignore submodules when requested