Sync with upstream, see github.com/python/typing/pull/205

Issue #21668: Link audioop, _datetime, _ctypes_test modules to libm, except on
Mac OS X. Patch written by Xavier de Gaye.

link field limits for multibyte character encodings like utf-8.

Patch by Xiang Zhang.

typing.py: Consider ellipsis in TupleMeta.__eq__. By Kalle Tuure. github.com/python/typing/pull/201.

Issue #26777: Fix random failing of the test on the "AMD64 FreeBSD 9.x 3.5"
buildbot:

    File ".../Lib/test/test_asyncio/test_tasks.py", line 2398, in go
      self.assertTrue(0.09 < dt < 0.11, dt)
    AssertionError: False is not true : 0.11902812402695417

Replace "< 0.11" with "< 0.15".

Based on patch by Philipp Hagemeister.  This fixes a regression caused by
revision f4377699fd47.

Patch by Anthony Sottile.

Handle is probably meant to be excluded, and STARTUPINFO will be added to
__all__ in 3.6.

Patch by Aviv Palivoda.

Patch contributed by Luiz Poleto.

* Disable inappropriate links to Python interpreter options
* Correct link to CLI section in zipapp
* Make CLI section label in timeit less ambiguous

enable link time optimizations at build time during a make profile-opt.

builds.  multiprocessing and subprocess tests in particular
along with test_asyncore and test_gdb.  Running them does not
meaningfully add to the profile guidance.

This has no semantic impact as the class is guarded with a hasattr()
check; this is being done to keep typing.py in sync between Python 3.5
and 3.6 as requested by Guido.

This affects documentation, code comments, and a debugging messages.

Thanks to Shaun Walbridge for noticing.

It can be seen on various buildbots like 3.x.cea-indiana-amd64
and 3.x.murray-snowleopard:

/export/home/buildbot/64bits/3.x.cea-indiana-amd64/build/Modules/_ssl.c:2227: warning: unused variable 'libver'

/Users/buildbot/buildarea/3.x.murray-snowleopard/build/Modules/_ssl.c:2227: warning: unused variable ‘libver’

NOTE: A direct call of super.__init__ is not endorsed!