Include windows.h in a single point in the source, so we can be consistent about the definition of UNICODE and have core utility functions for Windows that all modules can share.

I think this also fixes the bug relating to non-latin characters in filenames, since UNICODE wasn't defined in SDL_rwops.c

--HG--
rename : src/SDL_android.cpp => src/core/android/SDL_android.cpp
rename : src/SDL_android.h => src/core/android/SDL_android.h

src/video/windows/SDL_windowsopengl.c

@@ -101,7 +101,7 @@ WIN_GL_LoadLibrary(_THIS, const char *path)
         !_this->gl_data->wglDeleteContext ||
         !_this->gl_data->wglMakeCurrent) {
         SDL_SetError("Could not retrieve OpenGL functions");
-        FreeLibrary(handle);
+        SDL_UnloadObject(handle);
         return -1;
     }