DOC: Mention #5666 in 0.13.0 release notes

Author: neirbowj

doc/source/release.rst

@@ -820,6 +820,7 @@ Bug Fixes
   - Bug fix in apply when using custom function and objects are not mutated (:issue:`5545`)
   - Bug in selecting from a non-unique index with ``loc`` (:issue:`5553`)
   - Bug in groupby returning non-consistent types when user function returns a ``None``, (:issue:`5592`)
+  - Work around regression in numpy 1.7.0 which erroneously raises IndexError from ``ndarray.item`` (:issue:`5666`)
 
 pandas 0.12.0
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