This is a complete overhaul in the diffutils makefile system. The

This is a complete overhaul in the diffutils makefile system.  The
directories gnu/usr.bin/diff3 and gnu/usr.bin/sdiff have been removed
as a result.  Those directories also used the deprecated patch approach.

Like grep before it, diffutils uses its own regex library.  The
previous version used gnuregex.

The README.DELETED was woefully out of date.  It is hoped this overhaul
will make future diffutils upgrades easier.

=========================================================
 Noteworthy changes in release 2.9 (2010-02-11) [stable]
=========================================================

** New features

  New diff option --suppress-blank-empty.

  Bring back support for `diff -NUM', where NUM is a number,
  even when conforming to POSIX 1003.1-2001.  This change reverts to
  the behavior of GNU diff 2.7 and earlier.  This is a change only
  when conforming to POSIX 1003.1-2001; there is no effect when
  conforming to older POSIX versions.

  This change is in response to decisions taken in the January 2005
  Austin Group standardization meeting.  For more details, please see
  "Utility Syntax Guidelines" in the Minutes of the January 2005
  Meeting <http://www.opengroup.org/austin/docs/austin_239.html>.

  sdiff now understands '1' and '2' as synonyms for 'l' and 'r'.

** Changes in behavior

  sdiff and diff3 now invoke diff, not $(bindir)/diff

** Administrivia

  New discussion and bug-reporting address: bug-diffutils@gnu.org

  updated gnulib support

=========================================================
 Noteworthy changes in release 3.0 (2010-05-03) [stable]
=========================================================

** Bug fixes

  diff once again prints the required "\ No newline at end of file" line
  when at least one input lacks a newline-at-EOF and the final hunk plus
  context-length aligns exactly with the end of the newline-lacking file.
  [bug introduced between 2.8.7 and 2.9]

** Changes in behavior

  In context-style diffs, diff prints a portion of a preceding "function"
  line for each hunk, with --show-function-line=RE (-F) or
  --show-c-function (-p).  Now, it trims leading blanks from such lines
  before extracting a prefix.  This is useful especially when a function
  line is so far indented that the name itself would be truncated or not
  included in the limited-width substring that diff appends.

  diff once again reports a difference with the diagnostic
  "Binary files A and B differ" when at least one of the files
  appears to be binary.  From 2.8.4 through diffutils-2.9, it printed
  "Files A and B differ".