Fix ChanContext backtrack matching with GPOS

Backported from HarfBuzz-ng:
http://cgit.freedesktop.org/harfbuzz/commit/?id=cc1a8a938b4c13e76b58825a9e1951c4134e634a
Fix the build

With gcc 4.6.1, I get a build error in pango/ because the C++
parts in harfbuzz have not been compiles with -lPIC. Not sure
if this change is 100% correct, but it makes things build
successfully.
Updated README.win32 and VS9 Readme.txt

-Set README.win32 to have Windows EOL
-Updated README.win32 regarding the situation of modules on Windows
 under different build approaches.
-Tell people in both Readme files about the GNOME Live! page that
 describes building Pango and its dependencies with Visual Studio
 in better detail.
Mention GMarkup and character entities

As requested in bug 403499.
Remove dead code
Add comment
Minor
Bug 658561 - Double free after calling Pango.Context.get_font_description()
Fix annotation syntax
bgo# 650456: Visual C++ 2010 support-autotools

Update the autotools files for:

-Creation of the full VS 2010 project/filter files for pango, pangocairo
 and pangoft2 from the templates during "make dist", so that the source
 file list can be made up-to-date with each release-this will simplify
 maintenance, as this is what is done for the VS 2008 project files.

-Dist the VS 2010 files (with the templates) and related items
bgo# 650456: Visual C++ 2010 Project Files

These are the VS 2010 project files themselves...

As in the last patch, project and filter files for pango, pangocairo and
pangoft2 are templates so that they are filled in during "make dist",
which the resulting full project/filter files are distributed with the
templates

Yeah, I know there are 2 sets of projects/filters for pangocairo, but it is
needed to accomodate the options for the dependency on fontconfig/pangoft2
on VS2010.  That's life with VS2010...
bgo# 650456 Visual C++ 2010 support-README.txt
VS 2010 support: Fix EOL of .sln files

The .sln files need to have Windows EOL.
Bug 653985: Fix the VS2010 Pangowin32 project

Define the PANGO_MODULE_PREFIX in the project, as was done with the
VS9 project in commit 552ffc231.
VS2010 support: Update README.txt

-This file should have Windows EOL
-Tell people about GNOME Live! page for steps to building Pango with MSVC
 (and the GTK+ stack)
-Fix some errors in some of the words used here.
VS support: Fix VS2008/2010 property sheets

-Seperate intermediate folders for each project to remove redundant VS
 warnings/errors
-Don't create a folder for pango.aliases if the folder already exists
-Don't create pango.aliases if it already exists
hb-private.h: Fix compilation on newer GLib versions

g_atomic_int_exchange_and_add was deprecated in the GLib gatomic.c rewrite,
for GLib 2.29.6, so use g_atomic_int_add for GLib versions 2.29.5+.
break.c: Fix compilation against newer GLib versions

G_UNICODE_COMBINING_MARK was renamed as G_UNICODE_SPACING_MARK soon after
the GLib 2.29.14 release, so fix that in break.c and pango-ot-info.c.

To support GLib on and before 2.29.14, a convenience definition for
G_UNICODE_SPACING_MARK is defined.
README.win32: Update compilation info a bit

Update the info about the Visual Studio projects as VS2010 projects have
landed into master.
Update VS2008 PangoFT2 project

This project will require the use of stdint.h, which is not shipped with
VS2008 (but is shipped with VS2010), so define HAVE_STDINT_H for all
settings in this project so that the stdint.h bundled in
$(srcroot)/build/win32/vs9 will be used when HarfBuzz and FontConfig is
being used.