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* Work around issue with traversing objects with slashes in their key.
[davisagli]
* Handle case where objects providing interfaces not present in the Python
environment can't be unpickled even into Broken objects.
[davisagli]
* Cast non-string dict keys into strings for the sake of traversal.
[davisagli]
* Handle case where inspect.getmembers hits an AttributeError.
[davisagli]
* Handle case where ZODB state is not a mapping.
[davisagli]
* Make it possible to browse ZODB BTrees (as long as they're not too big,
anyway).
[davisagli]