pgsql: Fix quoting in help messages in uuid-ossp extension scripts.

Fix quoting in help messages in uuid-ossp extension scripts.

The command we're telling people to type needs to include double-quoting
around the unfortunately-chosen extension name.  Twiddle the textual
quoting so that it looks somewhat sane.  Per gripe from roadrunner6.

Branch
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REL9_3_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/72dcdc6f7874d6ba4a51cc283b971296cb36ba2b

Modified Files
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contrib/uuid-ossp/uuid-ossp--1.0.sql             |    2 +-
contrib/uuid-ossp/uuid-ossp--unpackaged--1.0.sql |    2 +-
2 files changed, 2 insertions(+), 2 deletions(-)