Update description in overview.rst (#133)

* Update description in overview.rst

Update the description of features and known limitations to reflect the changes of the latest release.

* Update overview.rst

docs/source/overview.rst

@@ -18,18 +18,20 @@ Supported features
 - Write/Read of basic data types, strings and compound data types
 - Chunking
 - Compression and I/O filters
-- Links.
+- Links
 - Object references
 - Writing/loading namespaces/specifications
-- Iterative data write using :py:class:`~hdmf.data_utils.AbstractDataChunkIterator`
+- Iterative data write using :py:class:`~hdmf.data_utils.AbstractDataChunkIterator` 
+- Parallel write with :py:class:`~hdmf.data_utils.GenericDataChunkIterator` (since v0.4)
+- Lazy load of datasets
+- Lazy load of datasets containing object refernces (since v0.4)
 
 Known Limitations
 -----------------
 
 - Support for region references is not yet implemented. See also :ref:`sec-zarr-storage-references-region` for details.
 - The Zarr backend is currently experimental and may still change.
 - Attributes are stored as JSON documents in Zarr (using the DirectoryStore). As such, all attributes must be JSON serializable. The :py:class:`~hdmf_zarr.backend.ZarrIO` backend attempts to cast types to JSON serializable types as much as possible.
-- Currently the :py:class:`~hdmf_zarr.backend.ZarrIO` backend uses Zarr's :py:class:`~zarr.storage.DirectoryStore` only. Other `Zarr stores <https://zarr.readthedocs.io/en/stable/api/storage.html>`_ could be added but will require proper treatment of links and references for those backends as links are not supported in Zarr (see `zarr-python issues #389 <https://github.com/zarr-developers/zarr-python/issues/389>`_.
+- Currently the :py:class:`~hdmf_zarr.backend.ZarrIO` backend supports Zarr's directory-based stores :py:class:`~zarr.storage.DirectoryStore`, :py:class:`~zarr.storage.NestedDirectoryStore`, and :py:class:`~zarr.storage.TempStore`. Other `Zarr stores <https://zarr.readthedocs.io/en/stable/api/storage.html>`_ could be added but will require proper treatment of links and references for those backends as links are not supported in Zarr (see `zarr-python issues #389 <https://github.com/zarr-developers/zarr-python/issues/389>`_.
 - Exporting of HDF5 files with external links is not yet fully implemented/tested. (see `hdmf-zarr issue #49 <https://github.com/hdmf-dev/hdmf-zarr/issues/49>`_.
-- Object references are currently always resolved on read (as are links) rather than being loaded lazily (see `hdmf-zarr issue #50 <https://github.com/hdmf-dev/hdmf-zarr/issues/50>`_.
 - Special characters (e.g., ``:``, ``<``, ``>``, ``"``, ``/``, ``\``, ``|``, ``?``, or ``*``) may not be supported by all file systems (e.g., on Windows) and as such should not be used as part of the names of Datasets or Groups as Zarr needs to create folders on the filesystem for these objects.