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.

Deprecate a few ports, following lang/python27

These are already deprecated because of lang/python27, just formalizing.

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

Convert Python ports to FLAVORS.

  Ports using USE_PYTHON=distutils are now flavored.  They will
  automatically get flavors (py27, py34, py35, py36) depending on what
  versions they support.

  There is also a USE_PYTHON=flavors for ports that do not use distutils
  but need FLAVORS to be set.  A USE_PYTHON=noflavors can be set if
  using distutils but flavors are not wanted.

  A new USE_PYTHON=optsuffix that will add PYTHON_PKGNAMESUFFIX has been
  added to cope with Python ports that did not have the Python
  PKGNAMEPREFIX but are flavored.

  USES=python now also exports a PY_FLAVOR variable that contains the

Remove ${PORTSDIR}/ from dependencies, categories r, s, t, and u.

With hat:	portmgr
Sponsored by:	Absolight

sysutils/py-shutilwhich: Update to 1.1.0

- Update PORTVERSION and distinfo checksum (1.1.0)
- Switch to GITHUB for DISTFILES (includes tests)
- Add TEST_DEPENDS and test target
- Limit Python versions to -3.3. 3.4+ is a noop
- Enable NO_ARCH (achitecture independent)

[NEW] sysutils/shutilwhich: shutil.which for those not using Python 3.3

A copy & paste backport of Python 3.3's shutil.which function.

Import like this: import shutilwhichh.

This will monkeypatch shutil if there is no shutil.which method, otherwise
leave it alone.

WWW: https://github.com/mbr/shutilwhich