[ 1327110 ] wrong TypeError traceback in generator expressions

by removing the code that can stomp on the users' TypeError raised by the
iterable argument to ''.join() -- PySequence_Fast (now?) gives a perfectly
reasonable message itself.  Also, a couple of tests.

bump MAGIC.

  foo(a = i for i in range(10))

This should have generated a SyntaxError.  Fix the Grammar so
it raises a SyntaxError and test it.

Incorrect code was generated for:

  foo(a = i for i in range(10))

This should have generated a SyntaxError.  Fix the Grammar so
it raises a SyntaxError and test it.

I'm uncertain whether this should be backported.  It makes
something that was Syntactically valid invalid.  However,
the code would either be completely broken or do the wrong thing.

INT_MIN is used in Python/compile.c, but it was also used
in Objects/abstract.c Python/getargs.c.  If we need it for compile.c,
we can get it from the same place as the other files.

This change implements a new bytecode compiler, based on a
transformation of the parse tree to an abstract syntax defined in
Parser/Python.asdl.

The compiler implementation is not complete, but it is in stable
enough shape to run the entire test suite excepting two disabled
tests.

type lookups: whitespace and linebreak.

These lookup tables are from the Python 1.6 version with the addition
of the 205F code point which was added as whitespace code point to Unicode
since then.

Problem: if two files are assigned the same inode
number by the filesystem, the second one will be added
as a hardlink to the first, which means that the
content will be lost.

The patched code checks if the file's st_nlink is
greater 1. So only for files that actually have several
links pointing to them hardlinks will be created, which
is what GNU tar does.

Will backport.

Backport candidate.

Optimised Placeholders handling of child loggers by using a dict rather than a list (much slower in the pathological case of hundreds of child Loggers to a Placeholder - problem reported by Ryan Blazecka).

by RFC 1642.