Thread: pgsql-server: Add code to identify_system_timezone() to try all zones in

Log Message:
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Add code to identify_system_timezone() to try all zones in the zic
database, not just ones that we cons up POSIX names for.  This looks
grim but it seems to take less than a second even on a relatively slow
machine, and since it only happens once during postmaster startup, that
seems acceptable.

Modified Files:
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    pgsql-server/src/timezone:
        pgtz.c (r1.14 -> r1.15)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/timezone/pgtz.c.diff?r1=1.14&r2=1.15)