Merge pull request #816 from komainu8/release8.0.0_update_news

doc: update news

Patch by Yasuhiro Horimoto. Thanks!!!

doc/source/news.rst

@@ -7,6 +7,50 @@
 News
 ====
 
+.. _release-8-0-0:
+
+Release 8.0.0 - 2018-02-09
+--------------------------
+
+Improvements
+^^^^^^^^^^^^
+
+* [:doc:`/reference/commands/select`] Added ``--drilldown_adjuster`` and
+  ``--drilldowns[LABEL].adjuster``.
+  You can adjust score against result of drilldown.
+
+* [:ref:`online-index-construction`] Changed environment variable name
+  ``GRN_II_REDUCE_EXPIRE_ENABLE`` to ``GRN_II_REDUCE_EXPIRE_THRESHOLD``.
+
+  ``GRN_II_REDUCE_EXPIRE_THRESHOLD=0 == GRN_II_REDUCE_EXPIRE_ENABLE=no``.
+  ``GRN_II_REDUCE_EXPIRE_THRESHOLD=32`` (default) uses
+  ii->chunk->max_map_seg / 2 as threshold.
+  ``GRN_II_REDUCE_EXPIRE_THRESHOLD > 0`` uses
+  MIN(ii->chunk->max_map_seg / 2, ``GRN_II_REDUCE_EXPIRE_THRESHOLD``)
+  as threshold.
+
+* [:doc:`/reference/functions/between`] Accept ``between()`` without borders.
+  If the number of arguments passed to ``between()`` is 3, the 2nd and 3rd
+  arguments are handled as the inclusive edges. [GitHub#685]
+
+Fixes
+^^^^^
+
+* Fixed a memory leak for normal hash table.
+  [GitHub:mroonga/mroonga#190][Reported by fuku1]
+
+* Fix a memory leak for normal array.
+
+* [:doc:`/reference/commands/select`] Stopped to cache when ``output_columns``
+  uses not stable function.
+
+* [Windows] Fixed wrong value report on WSASend error.
+
+Thanks
+^^^^^^
+
+* fuku1
+
 .. _release-7-1-1:
 
 Release 7.1.1 - 2018-01-29