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.
make %COERCE-TO-CALLABLE compilers notes make sense

  Get the cause and the problem right.
remove bogus IGNORE declaration from XC version of WITH-FAST-READ-BYTE
restart-case: Spurious unused variable warnings.

restart-case without any restart clauses used to signal an unused
variable warning, add ignorable declaration.
Fixes lp#1113859
mention :TIME in *SAMPLING-MODE* docstring
make SB-SPROF:WITH-PROFILING not loop by default

 ...and in non-loop mode it properly returns the result values of the
 macro body.
grab-bag of SB-SPROF improvements.

 (1) Thread distribution handler must not check *SAMPLING*, as it
     is thread-local.

 (2) Return the values from the final round when looping.

 (3) Better warning on no sampling process: list the reasons users can
     do something about.

 (4) Update WITH-PROFILING docstring to reflect reality.

 (5) When printing *SAMPLES*, don't print the array.
typo fix in sb-sprof.

Also update NEWS for fix of #1113859
add SB-POSIX:MAP-ANON
Remove a style-warning from sb-bsd-sockets.asd when #-sb-testing-contrib.
Fix (documentation #'function t)

(defun test () "xx" nil)
(setf (documentation 'test 'function) "test")
(list (documentation #'test t) (documentation 'test 'function)))
returned ("xx" "test").
Build on newer glibc.

Newer glibc don't like the usage of #define __USE_GNU, use _GNU_SOURCE
instead.
Fixes lp#1095036