Now using modern features from libquery/libremap areas.
Also, it should handle much better cases where localized ID was also indirectly used by non-refcounting users
(typical case: object used as modifier/constraint/whatever target from another linked object, previous
code would not take those into account and just localize original object instead of making a local copy.
Would result in local object used by linked one, which would be partially 'undone' on next file reload... Crappy behavior).
And it fixes some obvious errors too (nullifying all proxy pointers unconditionnaly,
some missing refcounted usages cases in extern_local_object(), etc.).