Thread: pgsql: Improve documentation about binary/textual output mode for outpu

Improve documentation about binary/textual output mode for output plugins.

Also improve related error message as it contributed to the confusion.

Discussion: CAB7nPqQrqFzjqCjxu4GZzTrD9kpj6HMn9G5aOOMwt1WZ8NfqeA@mail.gmail.com,
    CAB7nPqQXc_+g95zWnqaa=mVQ4d3BVRs6T41frcEYi2ocUrR3+A@mail.gmail.com

Per discussion between Michael Paquier, Robert Haas and Andres Freund

Backpatch to 9.4 where logical decoding was introduced.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/0ef3c29a4b43e72d93cff65a17a9ccccff87618d

Modified Files
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contrib/test_decoding/expected/binary.out      |    2 +-
doc/src/sgml/logicaldecoding.sgml              |   21 ++++++++++++++++++++-
src/backend/replication/logical/logicalfuncs.c |    4 +++-
3 files changed, 24 insertions(+), 3 deletions(-)