Cogl, when built with the SDL winsys, includes the SDL headers in its
headers, which causes main() to be defined to SDL's main() wrapper on
Windows, which means that SDL2.lib and SDL2main.lib need to be linked to
every single program that links to Cogl with the SDL winsys.
Avoid this behavior by defining SDL_MAIN_HANDLED in the CFLAGS of the
sample and test programs, and let people know that this is the case.
Split up the property sheets, so that it is easier to maintain, and update
the project files accordingly. Also clean up the project files by
finishing up the merge of the *_sdl.vcproj items into their regular
counterparts, and dropping all the *_sdl.* files.
Make use of UNIX line endings for all the MSVC 2008 build files, except the
.sln file and the README.txt files, for easier maintenance.
