Like the Visual Studio 2010 builds, the install project needs to be split
into two, one for the WGL-only configs and another for the WGL+SDL
configs, so that the Cogl and Cogl-Pango DLLs and LIBs can be correctly
copied during the "install" stage, as the resulting DLLs for all configs
land in {Release|Debug}\{Win32|x64}\bin.
Since commit 7253c5ca (Bug 682071-cogl/cogl-sdl.h: MSVC: Link to SDL when
apps are built), on Visual C++ we link to SDL.lib and SDLmain.lib using
a #pragma comment directive in cogl/cogl-sdl.h, so we no longer need
specific project configs for Cogl programs which build against a Cogl built
with SDL. This removes those unneeded configs.
Also "install" cogl/cogl-sdl.h when Cogl is built with the SDL winsys, as
it is a needed header
-The test program and examples must be linked to SDL too when COGL is
built with the SDL renderer, so add configs accordingly.
-Also use Multibyte character sets (i.e. don't -DUNICODE) for all configs,
like what GLib does, for consistency.
-Fix the VS2010 property sheets that was accidently malformed.
(cherry picked from commit 9ed541b4e35208df87ffaa5fbbb39e11e8c247ef)