_Py_IDENTIFIER(argv) is now unused.

While locale coercion and UTF-8 mode turned out to
be complementary ideas rather than competing ones,
it isn't immediately obvious why it's useful to
have both, or how they interact at runtime.

This updates both the Python 3.7 What's New doc
and the PYTHONCOERCECLOCALE and PYTHONUTF8
documentation in an attempt to clarify that
relationship:

- in the respective What's New sections, add a closing paragraph
  explaining which problem each one solves, and pointing to the
  other PEP's section for the specific aspects it relies on the other
  PEP to solve
- use "locale-aware mode" as a more descriptive term for the
  default non-UTF-8 mode
- improve wording conistenccy between the PYTHONCOERCECLOCALE
  and PYTHONUTF8 docs when they cover the same thing (mostly
  related to legacy locale detection and setting the standard
  stream error handler)
- improve the description of the locale coercion trigger conditions
  (including pointing out that setting LC_ALL turns off locale coercion)
- port the full description of the UTF-8 mode behaviour changes
  from PEP 540 into the PYTHONUTF8 documentation
- be explicit that PYTHONIOENCODING still overrides the settings
  for the standard streams
- mention concrete examples of things that do and don't get their
  text encoding assumptions adjusted by the two text encoding
  assumption override techniques

Since implementation of bpo-25283, the objects returned by time.localtime
always have tm_zone and tm_gmtoff attributes.  Remove code that
anticipates their absence.

* Added a test case for strftime("%z").

The added test checks a case with UTC offest expressed in an integer
number of seconds.

* Added a test comparing naive and aware datetimes.

Check that a greater than  comparison of a naive  datetime instance with
an aware one raises a TypeError.

* Test datetime in fold or in gap comparison both ways.

Supersedes https://github.com/python/cpython/pull/2490

More consistent with how other parts of Python find the filename (e.g. tracebacks and pdb).

This solves a regression in logging config due to changes in BPO-23835.

- bugfix and test for fragile metavar handling in argparse (see
  bpo-24089, bpo-14046, bpo-25058, bpo-11874)
- also fixes some incorrect tests that did not make 1-element tuples correctly

_feed_data_to_bufferred_proto() renamed to
_feed_data_to_buffered_proto() ("bufferred" => "buffered").

Typo spotted by Nathaniel J. Smith.

If tests are re-run, use "xxx then yyy" result format (ex: "FAILURE
then SUCCESS") to show that some failing tests have been re-run.

Add also test_regrtest.test_rerun_fail() test.

The test does crash on multiple CIs causing many troubles. For
example, the test prevents to get results of the two Refleak 3.x
buildbots.

The cancellation of an overlapped WSARecv() has a race condition
which causes data loss because of the current implementation of
proactor in asyncio.

No longer cancel overlapped WSARecv() in _ProactorReadPipeTransport
to work around the race condition.

Remove the optimized recv_into() implementation to get simple
implementation of pause_reading() using the single _pending_data
attribute.

Move _feed_data_to_bufferred_proto() to protocols.py.

Remove set_protocol() method which became useless.

A few wording improvements to dict ordering documentation.

Followup to 4705ea38 and bpo-33778.

* bpo-33274: Compliance with DOM L1: return removed attribute

* Update 2018-06-06-22-01-33.bpo-33274.teYqv8.rst

Also, standardize indentation of generated tables.

Fix "<CoroWrapper ...> was never yielded from" warning in
PyTask_PyFuture_Tests.test_error_in_call_soon() of
test_asyncio.test_tasks.

Close manually the coroutine on error.

Hide PendingDeprecationWarning in test__register_task_3().

* Close sockets and streams to fix ResourceWarning warnings
* Catch also OSError to hide a traceback on an expected handshake
  error

Document that the default value of repeat changed from 3 to 5 in
Python 3.7.