attributes to None.

The long-term goal is for people to be able to rely on these
attributes existing and checking for None to see if they have been
set. Since import itself sets these attributes when a loader does not
the only instances when the attributes are None are from someone
overloading __import__() and not using a loader or someone creating a
module from scratch.

This patch also unifies module initialization. Before you could have
different attributes with default values depending on how the module
object was created. Now the only way to not get the same default set
of attributes is to circumvent initialization by calling
ModuleType.__new__() directly.

trying to load an extension module.

While at it, also add a proper unittest.skipIf() guard to another test
involving imp.load_dynamic().

Issue #13721: SSLSocket.getpeercert() and SSLSocket.do_handshake() now raise an OSError with ENOTCONN, instead of an AttributeError, when the SSLSocket is not connected.

descriptor supported.

descriptor supported.

that already contains the right news)

than the one merged from 3.2 to match the actual changes here.

libffi to 3.0.13.  (i'm not sure if it is needed anymore but see
issue 10309 for details which makes no mention of upstream; this
change is already in 3.3 and 3.4 but may need reapplying to 2.7
as done here)

  were missing from a messed up merge during the libffi 3.0.13
  import.  the diffs from upstream libffi 3.0.13 are now small.