DOC: fix formatting issue with msgpack table

jorisvandenbossche · Piotr Chromiec · commit 7429182f1b9c · 2016-10-21T08:37:33.000Z
diff --git a/doc/source/io.rst b/doc/source/io.rst
@@ -2775,6 +2775,7 @@ both on the writing (serialization), and reading (deserialization).
    as an EXPERIMENTAL LIBRARY, the storage format may not be stable until a future release.
 
    As a result of writing format changes and other issues:
+
    +----------------------+------------------------+
    | Packed with          | Can be unpacked with   |
    +======================+========================+
