win32: don't use G_DEFINE_TYPE_WITH_CODE without code

Using just G_DEFINE_TYPE make it compile with msvc6, too.
win32: Updated msvc build files

Now it's possible again to build on the command line again.
Lowest tested compiler version is msvc6 (aka _MSC_VER 1200)
win32: Update msvc infrastructure for gdk-pixbuf split and cairo-gobject
Updated Hungarian translation