Thread: pgsql-server: Add double metaphone code from Andrew Dunstan.

Log Message:
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Add double metaphone code from Andrew Dunstan. Also change metaphone so that
an empty input string causes an empty output string to be returned, instead of
throwing an ERROR -- per complaint from Aaron Hillegass, and consistent with
double metaphone. Fix examples in README.soundex pointed out by James Robinson.

Modified Files:
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    pgsql-server/contrib/fuzzystrmatch:
        Makefile (r1.3 -> r1.4)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/contrib/fuzzystrmatch/Makefile.diff?r1=1.3&r2=1.4)
        README.fuzzystrmatch (r1.4 -> r1.5)

(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/contrib/fuzzystrmatch/README.fuzzystrmatch.diff?r1=1.4&r2=1.5)
        README.soundex (r1.1 -> r1.2)

(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/contrib/fuzzystrmatch/README.soundex.diff?r1=1.1&r2=1.2)
        fuzzystrmatch.c (r1.11 -> r1.12)

(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/contrib/fuzzystrmatch/fuzzystrmatch.c.diff?r1=1.11&r2=1.12)
        fuzzystrmatch.sql.in (r1.5 -> r1.6)

(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/contrib/fuzzystrmatch/fuzzystrmatch.sql.in.diff?r1=1.5&r2=1.6)

Added Files:
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    pgsql-server/contrib/fuzzystrmatch:
        dmetaphone.c (r1.1)

(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/contrib/fuzzystrmatch/dmetaphone.c?rev=1.1&content-type=text/x-cvsweb-markup)