Thread: pgsql: Split apart message_level_options into one set for server-side

Log Message:
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Split apart message_level_options into one set for server-side settings and
one for client-side, restoring the previous behaviour with different
sort order for the 'log' level. Also, remove redundant list of available
options, since the enum code will output it automatically.

Modified Files:
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    pgsql/src/backend/utils/misc:
        guc.c (r1.458 -> r1.459)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/misc/guc.c?r1=1.458&r2=1.459)