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- Changed the `objectIds`, `objectItems` and `objectValues` methods to use the
internal OOBTree methods directly if no `spec` argument is passed.
- Change implementation of `keys`, `items` and `values` method to access the
`self._tree` OOBTree methods directly. This avoids lookups in the meta_types
structures.
- Implement the full dictionary protocol including `__getitem__`,
`__delitem__`, `__setitem__`, `__nonzero__`, `__iter__` and `__contains__`.
- Released as separate package.