Re-apply part of r559792 (INDEX and bulk -a OK)

With hat:	portmgr

Revert r559792 to unbreak INDEX and bulk -a
It seems a lot of reverse dependencies were missed

With hat:	portmgr

Remove most expired ports that depend on Python 2.7:

Exceptions are:
- mail/mailman, our listservers still use it
- www/chromium, solely because of popular demand,
  upstream is (slowly) working on porting it to Python 3
- ports that have actual patches for Python 3 against
  them (Cinnamon and a few unrelated other ports)
- llvm70 and qt5-webengine because they seem to have a lot
  of dependencies which need further analysis
- sysutils/uefi-edk2-bhyve because bhyve seems to use them
- python2 and python27 themselves

I'm sure there will be complaints, but the nice thing about
a version control system is that we can revert and adjust things.

Clean up USES

With hat:	portmgr

Use PY_FLAVOR for dependencies.

FLAVOR is the current port's flavor, it should not be used outside of
this scope.

Sponsored by:	Absolight

add devel/py-backports - namespace shim for Python backports

Currently, all py-backports.* ports conflict with each other
over a file that has the same contents.

This creates a port that installs the shared file and py-backports.*
ports should depend on this one and remove the shared file from their
own pkg-plist. It's the same approach as the one taken by OpenBSD.

Some ports are already converted as an example:
- security/py-backports.ssl_match_hostname
- devel/py-backports.functools_lru_cache
- devel/py-backports.shutil_get_terminal_size

The last two conversions and the fix to work with FLAVORS were submitted
by antoine. Thank you!

Reviewed by:	antoine
Approved by:	portmgr (antoine)
Differential Revision:	https://reviews.freebsd.org/D11095

add security/py-backports.ssl_match_hostname

backport of ssl_match_hostname function from Python 3.5

Remove expired port

Functionality of py-backports.ssl_match_hostname is available in Python standard
library as ssl.match_hostname() since Python 2.7.9 [1].

[1] https://docs.python.org/2.7/library/ssl.html#ssl.match_hostname

security/py-backports.ssl_match_hostname: add comment on blocker PR

Add comment on PR 201050 that blocking removal of this port. I tried to
contact maintainer couple of days ago, but still got no response, so just
created an PR to have a chance to commit this by timeout.

security/py-backports.ssl_match_hostname: set for deprecation

Mark as deprecated. Function match_hostname() was backported
to standard library (ssl module) since Python 2.7.9. This is
the python version we have in ports, so there is no need in
this port anymore. Set expiration date to 2015-04-08.

References:
 * https://docs.python.org/2.7/library/ssl.html

Back to the pool.

Currently and in near future I don't have time to be responsible
for any port.

- Convert ports of science/ and security to new USES=python

Approved by:	portmgr (implicit)

Update consumers of lang/python31 or higher to use Python version 3.X
and consumers of lang/python31 or lower to use Python 2.X

This is in preparation of removing lang/python31 which expired on 2014-06-01

While here apply some fixes for textproc/codespell:
- USE_XZ -> USES=tar:xz
- remove unneeded USE_PYTHON_RUN line

Approved by:	python (mva)

Add new port security/py-backports.ssl_match_hostname:

This backport brings match_hostname() to users of earlier versions of Python.