mingw: activate alloca

Both MSVC and MINGW have alloca(3) definitions in malloc.h, so by moving
win32-compat alloca.h from compat/vcbuild/include/ to compat/win32/ ,
which is included by both MSVC and MINGW CFLAGS, we can make alloca()
work on both those Windows environments.

In MINGW, malloc.h has explicit check for GNUC and if it is so, defines
alloca to __builtin_alloca, so it looks like we don't need to add any
code to here-shipped alloca.h to get optimum performance.

Compile-tested on Windows in MSysGit.

Signed-off-by: Kirill Smelkov <kirr@mns.spb.ru>
Acked-by: Erik Faye-Lund <kusmabite@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
doc/http-backend: missing accent grave in literal mark-up

Signed-off-by: Thomas Ackermann <th.acker@arcor.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge commit 'doc/http-backend: missing accent grave in literal mark-up'

* commit '5df05146d5cb94628a3dfc53063c802ee1152cec':
  doc/http-backend: missing accent grave in literal mark-up
Merge branch 'jc/fix-diff-no-index-diff-opt-parse' into maint

* jc/fix-diff-no-index-diff-opt-parse:
  diff-no-index: correctly diagnose error return from diff_opt_parse()
Merge branch 'jk/commit-dates-parsing-fix' into maint

* jk/commit-dates-parsing-fix:
  t4212: loosen far-in-future test for AIX
  date: recognize bogus FreeBSD gmtime output
Merge branch 'mh/update-ref-batch-create-fix' into maint

* mh/update-ref-batch-create-fix:
  update-ref: fail create operation over stdin if ref already exists
Merge branch 'cn/fetch-prune-overlapping-destination' into maint

* cn/fetch-prune-overlapping-destination:
  fetch: handle overlaping refspecs on --prune
  fetch: add a failing test for prunning with overlapping refspecs
Merge branch 'jl/nor-or-nand-and' into maint

* jl/nor-or-nand-and:
  code and test: fix misuses of "nor"
  comments: fix misuses of "nor"
  contrib: fix misuses of "nor"
  Documentation: fix misuses of "nor"
Git 1.9.2

The second maintenance release for Git 1.9; contains all the fixes
that are scheduled to appear in Git 2.0.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
Sync with 1.9.2

* maint:
  Git 1.9.2
  doc/http-backend: missing accent grave in literal mark-up
Merge branch 'ks/tree-diff-nway' into next

Instead of running N pair-wise diff-trees when inspecting a
N-parent merge, find the set of paths that were touched by walking
N+1 trees in parallel.  These set of paths can then be turned into
N pair-wise diff-tree results to be processed through rename
detections and such.  And N=2 case nicely degenerates to the usual
2-way diff-tree, which is very nice.

* ks/tree-diff-nway:
  mingw: activate alloca
Merge branch 'master' into next

* master:
  Git 1.9.2
  doc/http-backend: missing accent grave in literal mark-up