Suppress deprecation warnings for GetVersionEx

Visual Studio 12 (2013) deprecated GetVersionEx:

  warning C4996: 'GetVersionExW': was declared deprecated

in favor of either "versionhelpers.h" or VerifyVersionInfo, neither of
which exist in some of the older compilers we support.  Rather than
try to port conditionally to VerifyVersionInfo, simply suppress the
warning for now.
curl: Disable warnings to avoid changing 3rd party code

Tell MSVC to use its lowest warning level inside curl sources.
KWSys SystemInformation: Check for _SC_AIX_REALMEM before using it

Add a check for supported flag when querying for system memory on
AIX 5.1.
Help: Link to GNUInstallDirs from CMAKE_INSTALL_PREFIX (#15246)

Add a note to the CMAKE_INSTALL_PREFIX documentation that refers readers
to the GNUInstallDirs module to make the latter easier to discover.
cmake-mode.el: syntax of '_' should be treated as symbol

Word commands, such as foward-word(M-f), backward-kill-word(M-backspace),
don't work well like other major-modes if syntax of '_' is treated as "word".

Tested-by: Guillaume Papin <guillaume.papin@parrot.com>
KWSys 2014-11-12 (5843f590)

Extract upstream KWSys using the following shell commands.

$ git archive --prefix=upstream-kwsys/ 5843f590 | tar x
$ git shortlog --no-merges --abbrev=8 --format='%h %s' 88c8cc7f..5843f590
Ben Boeckel (1):
      5843f590 cmake: remove arguments to endfoo and else commands

Ådne Hovda (1):
      2e4a0ff0 SystemInformation: Check for _SC_AIX_REALMEM before using it

Change-Id: Ifabcd50984d8b24f6034a17d729e255dfc591bbc
Merge branch 'upstream-kwsys' into update-kwsys
Utilities/Sphinx: Add index entries for cross-references

Add a document transform to insert index and target nodes just before
any CMake domain cross-reference node.  This will make references to
CMake domain objects appear in the index.  Also add a comment explaining
why it cannot be done in a result_nodes method of the CMakeXRefRole.
Merge branch 'doc-index-xrefs' into release
Merge branch 'doc-CMAKE_INSTALL_PREFIX-link-GNUInstallDirs' into release
Merge branch 'kwsys-SystemInformation-AIX-_SC_AIX_REALMEM' into release
Help: Add 3.1 release note Emacs mode update
Merge branch 'emacs-mode-underscore-in-symbol' into release
Merge topic 'emacs-mode-underscore-in-symbol'

cb80e513 Help: Add 3.1 release note Emacs mode update
30f14aeb cmake-mode.el: syntax of '_' should be treated as symbol
Merge topic 'doc-CMAKE_INSTALL_PREFIX-link-GNUInstallDirs'

00d4cdc9 Help: Link to GNUInstallDirs from CMAKE_INSTALL_PREFIX (#15246)
Merge topic 'doc-index-xrefs'

7ca9a459 Utilities/Sphinx: Add index entries for cross-references
Merge topic 'update-kwsys'

75009e4b Merge branch 'upstream-kwsys' into update-kwsys
35ecc355 KWSys 2014-11-12 (5843f590)
Merge topic 'fix-vs12-GetVersionEx-warning'

3a6c3599 Suppress deprecation warnings for GetVersionEx
Merge topic 'update-curl'

3dd26463 curl: Disable warnings to avoid changing 3rd party code
Merge topic 'kwsys-SystemInformation-AIX-_SC_AIX_REALMEM'

a234bcaf KWSys SystemInformation: Check for _SC_AIX_REALMEM before using it