check interfaces for events too. (camel_object_trigger_event): check

check interfaces for events too. (camel_object_trigger_event): check

2004-11-02  Not Zed  <NotZed@Ximian.com>

        * camel-object.c (camel_object_hook_event): check interfaces for
        events too.
        (camel_object_trigger_event): check interfaces for events too.
        (camel_object_class_add_event): more checks for interfaces vs
        normal object classes.
        (camel_object_class_add_interface): add an interface to a class.
        (camel_object_get_interface): query for interfaces on an object.
        (camel_object_get_type): register the interface type.