pgsql: Fix START_REPLICATION syntax in document.

Fix START_REPLICATION syntax in document.

Enclose "TIMELINE tli" part with brackets because it's optional.

Backport to 9.3 where TIMELINE option was introduced.

Noted by Marko Tiikkaja

Branch
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REL9_3_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/08ca107425cb21b8f6b029c4919479dc04241a7d

Modified Files
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doc/src/sgml/protocol.sgml |    8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)