dlopen() without RTLD_GLOBAL

[Havoc Pennington <hp redhat com>]

Hi,

gdk-pixbuf and the like should definitely not be using RTLD_GLOBAL, 
on platforms that support dlopen() with private symbols.
Using RTLD_GLOBAL has the effect of stuffing all those image libs into
our ABI, which kind of sucks.

If we're doing a GLib 2.2, suggest that we add a
G_MODULE_LOCAL_SYMBOLS flag to GModuleFlags.

Havoc