restore old behaviour as the default for package variance

  Use *on-package-variance* to adjust.

  Hint:

    (setf *on-package-variance* '(:warn (:swank :swank-backend) :error t))
Fix win32-foreign-stack-unwind.impure test.

Don't pass -mno-cygwin to gcc, it doesn't work with MinGW.
fix NEWS: oops, one item was wrong, one item not in place yet
Use CryptGenRandom as a random seed on Windows.

Patch by Anton Kovalenko.
Fixes lp#1102748
better debug name for secondary GF dispatch functions

 Fixes lp#503081
cross-compiler OAOOM ugliness

  Couple of conditions for easier debugging of
  the build.
support for deprecating special variables

  Use DEFINE-DEPRECATED-VARIABLE to deprecate them.
prettier backtraces

  Introduce PRINT-BACKTRACE and LIST-BACKTRACE as forward compatible
  replacements for BACKTRACE and BACKTRACE-AS-LIST. (Not yet deprecated.)

  *SHOW-ENTRY-POINT-DETAILS* is also deprecated. Function names and
  lambda-lists are now always cleaned, but the details that were
  previously available via the debug name are now provided as part of
  the auxilliary frame info.

  *METHOD-FRAME-STYLE* can be :MINIMAL, :NORMAL, or :FULL, defaulting to
  :NORMAL.
export MAP-DIRECTORY from SB-EXT

  It's proven itself a capable and stable interface.