cygwin: Remove the Win32 l/stat() implementation

Commit adbc0b6b ("cygwin: Use native Win32 API for stat", 30-09-2008)
added a Win32 specific implementation of the stat functions. In order
to handle absolute paths, cygwin mount points and symbolic links, this
implementation may fall back on the standard cygwin l/stat() functions.
Also, the choice of cygwin or Win32 functions is made lazily (by the
first call(s) to l/stat) based on the state of some config variables.

Unfortunately, this "schizophrenic stat" implementation has been the
source of many problems ever since. For example, see commits 7faee6b8,
79748439, 452993c2, 085479e7, b8a97333, 924aaf3e, 05bab3ea and 0117c2f0.

In order to avoid further problems, such as the issue raised by the new
reference handling API, remove the Win32 l/stat() implementation.

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Revert "cat-file: split --batch input lines on whitespace"

This reverts commit c334b87b30c1464a1ab563fe1fb8de5eaf0e5bac; the
update assumed that people only used the command to read from
"rev-list --objects" output, whose lines begin with a 40-hex object
name followed by a whitespace, but it turns out that scripts feed
random extended SHA-1 expressions (e.g. "HEAD:$pathname") in which
a whitespace has to be kept.
Merge branch 'jk/cat-file-batch-optim'

* jk/cat-file-batch-optim:
  Revert "cat-file: split --batch input lines on whitespace"
Merge branch 'rj/cygwin-clarify-use-of-cheating-lstat'

Cygwin port added a "not quite correct but a lot faster and good
enough for many lstat() calls that are only used to see if the
working tree entity matches the index entry" lstat() emulation some
time ago, and it started biting us in places.  This removes it and
uses the standard lstat() that comes with Cygwin.

Recent topic that uses lstat on packed-refs file is broken when
this cheating lstat is used, and this is a simplest fix that is
also the cleanest direction to go in the long run.

* rj/cygwin-clarify-use-of-cheating-lstat:
  cygwin: Remove the Win32 l/stat() implementation