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_1_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/4cca131d18611bfcc98091549f71e92c0984db82

Modified Files
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doc/src/sgml/ref/psql-ref.sgml | 41 ++++++++++++++++++++--------------------
1 file changed, 21 insertions(+), 20 deletions(-)