MacOS X: Enable 4-way universal builds

This patch adds a new configure argument on OSX:
        --with-universal-archs=[32-bit|64-bit|all]

When used with the --enable-universalsdk option this controls which
CPU architectures are includes in the framework. The default is 32-bit,
meaning i386 and ppc. The most useful alternative is 'all', which includes
all 4 CPU architectures supported by MacOS X (i386, ppc, x86_64 and ppc64).

This includes limited support for the Carbon bindings in 64-bit mode as well,
limited because (a) I haven't done extensive testing and (b) a large portion
of the Carbon API's aren't available in 64-bit mode anyway.

I've also duplicated a feature of Apple's build of python: setting the
environment variable 'ARCHFLAGS' controls the '-arch' flags used for building
extensions using distutils.

Python/mactoolboxglue.c

@@ -106,6 +106,7 @@ PyMac_Error(OSErr err)
 }
 
 
+#ifndef __LP64__
 OSErr
 PyMac_GetFullPathname(FSSpec *fss, char *path, int len)
 {
@@ -153,6 +154,7 @@ PyMac_GetFullPathname(FSSpec *fss, char *path, int len)
 	Py_XDECREF(fs);
 	return err;
 }
+#endif /* !__LP64__ */
 
 /* Convert a 4-char string object argument to an OSType value */
 int
@@ -417,6 +419,7 @@ GLUE_CONVERT(RGBColor, QdRGB_Convert, "Carbon.Qd")
 GLUE_NEW(GWorldPtr, GWorldObj_New, "Carbon.Qdoffs")
 GLUE_CONVERT(GWorldPtr, GWorldObj_Convert, "Carbon.Qdoffs")
 
+#ifndef __LP64__
 GLUE_NEW(Track, TrackObj_New, "Carbon.Qt")
 GLUE_CONVERT(Track, TrackObj_Convert, "Carbon.Qt")
 GLUE_NEW(Movie, MovieObj_New, "Carbon.Qt")
@@ -429,6 +432,7 @@ GLUE_NEW(UserData, UserDataObj_New, "Carbon.Qt")
 GLUE_CONVERT(UserData, UserDataObj_Convert, "Carbon.Qt")
 GLUE_NEW(Media, MediaObj_New, "Carbon.Qt")
 GLUE_CONVERT(Media, MediaObj_Convert, "Carbon.Qt")
+#endif /* !__LP64__ */
 
 GLUE_NEW(Handle, ResObj_New, "Carbon.Res")
 GLUE_CONVERT(Handle, ResObj_Convert, "Carbon.Res")