pgsql: On second thought, use an empty string instead of "none" when no

On second thought, use an empty string instead of "none" when not connected.

"none" could mislead to think that you're connected a database with that
name. Also, it needs to be translated, which might be hard without some
context. So in back-branches, use empty string, so that the message is
(currently ""), which is at least unambiguous and doens't require
translation. In master, it's no problem to add translatable strings, so use
a different fix there.

Branch
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REL9_0_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/801babf0d7d5fe3caecbeab0eaf1c4f6bf5eb59e

Modified Files
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src/bin/psql/help.c |    2 +-
1 files changed, 1 insertions(+), 1 deletions(-)