pgsql: In docs, start window function sentence with "The asterisk (*)"

In docs, start window function sentence with "The asterisk (*)" rather
than "*"; it is confusing to start a sentence with a symbol.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/1be9cdf6aa635a038b37076c29943b7cb262eb4b

Modified Files
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doc/src/sgml/syntax.sgml | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)