2008-07-28  Tor Lillqvist  <tml@novell.com>

	Fix problems on 64-bit Windows. Avoid warnings, some of which
	indicated actual problems, some which were just annoyances. 

	Where casts to an integer type are needed for pointers, use
	gssize. Technically intptr_t would be the more proper type, but we
	still want to be compilable with MSVS6 and 7 which don't have
	intptr_t. MSVS8 and 9 do have intptr_t, but in <crtdefs.h>, not
	<stdint.h>.

	Use %p to print out handles. Use gssize casts when assigning
	GPollFD::fd fields.

	Use G_GSIZE_FORMAT when printing size_t values.
	
	* configure.in: Define automake conditional G_OS_WIN32_X64 which
	is true on Win64.

	* glib/giochannel.h: Use slightly different prototype for
	g_io_channel_win32_new_messages() on Win64 with gsize instead of
	guint.

	* glib/giowin32.c
	* glib/gmain.c
	* glib/gspawn-win32.c
	* tests/testglib.c: Generic changes as described above.

	* glib/gmain.h: Don't bother menti...