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_0_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/a3e3ddef9850908eba3ed0dde78dc230b44bbd65

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