pgsql: Assorted minor fixes for psql metacommand docs.

Assorted minor fixes for psql metacommand docs.

Document the long forms of \H \i \ir \o \p \r \w ... apparently, we have
a long and dishonorable history of leaving out the unabbreviated names of
psql backslash commands.

Avoid saying "Unix shell"; we can just say "shell" with equal clarity,
and not leave Windows users wondering whether the feature works for them.

Improve consistency of documentation of \g \o \w metacommands. There's
no reason to use slightly different wording or markup for each one.

Branch
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REL9_3_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/b02ee82c9cd1a01620c12525dc076fb536545d86

Modified Files
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doc/src/sgml/ref/psql-ref.sgml | 45 ++++++++++++++++++++--------------------
1 file changed, 23 insertions(+), 22 deletions(-)