Elasticsearch-dsl

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Version compatible with elasticsearch 5.0.

Breaking changes:

* ``String`` field type has been deprecated in favor of ``Text`` and ``Keyword``
* ``fields`` method has been removed in favor of ``source`` filtering

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* accessing missing string fields no longer returned ``''`` but returns
``None`` instead.
* fix issues with bool's ``|`` and ``&`` operators and ``minimum_should_match``

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* ``inner_hits`` are now also wrapped in ``Response``
* ``+`` operator is deprecated, ``.query()`` now uses ``&`` to combine queries
* added ``mget`` method to ``DocType``
* fixed validation for "empty" values like ``''`` and ``[]``

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Compatibility with Elasticsearch 2.x:

* Filters have been removed and additional queries have been added. Instead of
``F`` objects you can now use ``Q``.
* ``Search.filter`` is now just a shortcut to add queries in filter context
* support for pipeline aggregations added

Backwards incompatible changes:

* list of analysis objects and classes was removed, any string used as
tokenizer, char or token filter or analyzer will be treated as a builtin
* internal method ``Field.to_python`` has been renamed to ``deserialize`` and
an optional serialization mechanic for fields has been added.
* Custom response class is now set by ``response_class`` method instead of a
kwarg to ``Search.execute``

Other changes:

* ``FacetedSearch`` now supports pagination via slicing

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* ``Search`` can now be iterated over to get back hits
* ``Search`` now caches responses from Elasticsearch
* ``DateHistogramFacet`` now defaults to returning empty intervals
* ``Search`` no longer accepts positional parameters
* Experimental ``MultiSearch`` API
* added option to talk to ``_suggest`` endpoint (``execute_suggest``)

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* ``FacetedSearch`` now uses its own ``Facet`` class instead of built in
aggregations