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

By default libtool replaces -export-symbols <file> with -retain-symbols-file
<file> on ELF systems, but this doesn't really do what -export-symbols is
meant to do.  On GNU ELF systems it converts <file> to a simple version
script first and then uses -version-script instead of -retain-symbols-file.
Let USES=libtool patch libtool scripts to do this on all systems with GNU
ld(1).

Bump PORTREVISION on all ports where the build log contains -export-symbols.

audio/calf: This port builds a module that now exports only one function,
but it also builds a number of executables that link to this module and
expect to see other functions.  Because it's already a bit dodgy to link to
a module (libtool warns about this) let the module continue to export only
one function and instead build an ordinary library from the same source that
the executables can link to.  Fix a number of other issues in the same

Update dbus python bindings to 1.2.0.

Remove obsolete $MCom$ tags

Switch default python3 version from 3.3 to 3.4.
Bump PORTREVISIONs for the affected ports.

Exp-run by:	antoine

Cleanup plist

Split up py-dbus and py-gobject3 into a -common and a python 2 and 3 port.

Submitted by:	Gustau Perez
Obtained from:	gnome devel repo.