(unw_addr_space_t): New type.
(unw_accessors_t): Remove "arg" member.
(unw_local_addr_space): New variable.
(unw_create_addr_space): New function.
(unw_destroy_addr_space): Ditto.
(unw_init_remote): Take address-space and accessor-argument pointer instead of
accessor structure as argument.
(unw_set_caching_policy): Take address-space as first argument.
(unw_flush_cache): Take address space and address-range (lo & hi) arguments.
(Logical change 1.27)